Focus On Science Grade 9 (Teacher's Guide)

Teacher’s Guide Focus-on Science Grade 9 19 © Praxis Publishing Singapore Pte. Ltd. 8 The three main stages of birth are dilation, delivery of the baby, and delivery of the placenta. During dilation, the cervix expands and opens to allow the baby to pass through; during delivery, the baby is born; and during delivery of the placenta, the placenta is expelled from the uterus. Importance of Prenatal Care 9 Prenatal care is the healthcare and support given to pregnant women to ensure a healthy pregnancy and delivery. It includes regular check-ups, screening tests, and education on nutrition and exercise. Effects of Harmful Substances 10 Exposure to harmful substances such as alcohol, drugs and tobacco during pregnancy can have serious effects for both the mother and the developing foetus. These substances can increase the risk of birth defects, developmental delays and other health problems in the child. Extension / Follow-up Activities Risks and Complications of Pregnancy 1 Divide students into groups. 2 Ask each group to search for information about risks and complications of pregnancy. 3 Have students prepare a sheet about the risks and complications of pregnancy. The sheet should include the following information: • The name of the risk or complication • The cause of the risk or complication • The symptoms of the risk or complication • The treatment for the risk or complication 4 Ask each group to choose one volunteer to present the outcomes of their findings. This helps in developing their communication skills. 5 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Lesson 1.7 Common Disorders and Diseases of the Male and Female Reproductive Systems Learning Outcomes • Identify and describe some common disorders and diseases of the male and female reproductive systems • Explain the causes and symptoms for these reproductive disorders and diseases Key Understanding Some examples of female reproductive system diseases include endometriosis, polycystic ovary syndrome (PCOS), uterine fibroids, ovarian cysts and cervical cancer. These conditions can cause a range of symptoms such as pain, irregular periods, infertility and abnormal vaginal bleeding. Female reproductive system diseases can be caused by infections, hormonal imbalances, structural abnormalities, and lifestyle factors such as smoking and poor diet. Some examples of male reproductive system diseases include prostate cancer, testicular cancer and epididymitis. These conditions can have a significant impact on a man’s overall health and quality of life. Some of the causes of male reproductive system diseases include infections, hormonal imbalances and genetic factors. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 20 © Praxis Publishing Singapore Pte. Ltd. Induction 1 Begin by asking students to share what they already know about common disorders and diseases of the male and female reproductive systems. 2 Encourage students to share what they know about common disorders and diseases of the male and female reproductive systems. Teaching and Learning Activities Textbook pp. 21–22 1 Explain what a reproductive disorder or disease is. 2 Using the examples in the book, explore reproductive disorders or diseases with students. 3 Ask students to carry out Activity 1 and guide them to research on some other reproductive disorders or diseases, including their causes, symptoms, treatments and preventative measures. Students will enhance their digital skills with the research work using the Internet. Invite two groups to present their findings. 4 Guide students to analyse the following cases where students work in groups to diagnose and recommend treatment for a patient with a reproductive system disorder or disease. Case 1: A 32-year-old female experiences irregular menstrual cycles, weight gain and difficulty getting pregnant. Many cysts were found to grow on both the ovaries. Case 2: A 45-year-old male found a lump or swelling in his right testicle and experiences pain in the area. He also experiences a feeling of heaviness in the lower abdomen. 5 At the end of the lesson, encourage students to develop their critical thinking skills by answering the following questions. • What are some common disorders of the male reproductive system? Give two disorders. • What are some common disorders of the female reproductive system? Give two disorders. • What are the symptoms of polycystic ovary syndrome (PCOS)? • Does PCOS affect fertility? • What are the common causes of pelvic inflammatory disease (PID)? • What are the most common types of reproductive cancers? Give three examples of cancers. Assessment and Evaluation 1 Assess students’ understanding of all the concepts learned by observing their participation and responses in class discussions and activities. 2 Assess students’ collaboration skills and digital skills through Activity 1. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1−4 Workbook p. 15 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 21 © Praxis Publishing Singapore Pte. Ltd. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 The female reproductive system diseases include polycystic ovary syndrome (PCOS), uterine fibroids, pelvic inflammatory disease (PID), ovarian cancer and cervix abnormalities. 2 The male reproductive system diseases include prostate cancer, testicular cancer and epididymitis. 3 The causes of male and female reproductive system diseases can vary widely. Some common causes include infections, hormonal imbalances, genetic or congenital abnormalities, tumours, structural changes, lifestyle factors such as smoking and poor diet, and certain medications or medical treatments. 4 Polycystic ovary syndrome (PCOS) is a hormonal disorder that affects women of reproductive age. It is characterised by the presence of multiple cysts on the ovaries, irregular menstrual periods and high levels of male hormones in the body. 5 Uterine fibroids are non-cancerous tumours that develop in the uterus. They can cause heavy menstrual bleeding, frequent urination and infertility. 6 Pelvic inflammatory disease (PID) is an infection of the female reproductive system that can lead to infertility, lower abdominal pain and vaginal odour. It is usually caused by sexually transmitted infections such as chlamydia and gonorrhoea. 7 Reproductive cancers refer to cancers that affect the reproductive organs such as the cervix, ovaries, uterus, prostate and testicles. These types of cancers can cause symptoms such as abnormal bleeding or discharge, pain during urination and lumps in the affected area. 8 Congenital reproductive tract disorders are abnormalities that occur during foetal development and can affect the function of the reproductive system. Extension / Follow-up Activities Causes of Infertility 1 Ask students to work in groups. 2 Have each group research about the causes of infertility using the Internet. Prepare a presentation about at least five causes of infertility. 3 Ask each group to choose two representatives to present the outcomes of their findings. This helps in developing their communication skills. 4 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Lesson 1.8 Lifestyle Factors that Support the Reproductive System Learning Outcomes • Identify lifestyle factors that support the reproductive system • Explain how these lifestyle factors affect reproductive health • Explain how to keep our reproductive system healthy and prevent reproductive diseases • Apply this health knowledge to make reasoned decisions about their own reproductive health ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 22 © Praxis Publishing Singapore Pte. Ltd. Key Understanding Lifestyle factors that support the reproductive system include eating a healthy diet, maintaining good oral health, exercising regularly, getting enough sleep, practicing safe sex, avoiding smoking and excessive alcohol consumption, managing stress levels and getting regular health screenings. Induction 1 Begin by asking students to share what they already know about lifestyle factors that support the male and female reproductive systems. 2 Encourage students to share what they know about lifestyle factors that support the male and female reproductive systems. Teaching and Learning Activities Textbook pp. 23–24 1 Introduce lifestyle factors that affect the reproductive system using examples in the textbook. Explain how these factors can affect the health of the male and female reproductive systems. 2 Have students brainstorm ideas for other factors that could affect their reproductive health. Invite one or two students to share their ideas. 3 Guide students in creating a healthy meal plan that includes foods known to support reproductive health. Students can search for the information using the Internet. Suggestion: Foods such as leafy greens, fruits, nuts, whole grains and lean proteins can be added into the meal plan to support reproductive health. Limit processed foods and sugary drinks as they can have negative effects on fertility. 4 Guide students to analyse a few cases of individuals with reproductive health issues and identify potential lifestyle changes that could improve their reproductive health. Divide students into groups and assign each group a case study to analyse. Each group can then present their findings and recommendations to the class. Case 1: A woman has irregular periods. Suggestion: Adopt a healthy diet and exercise regularly to maintain a healthy weight. This also improves insulin sensitivity and regulates the menstrual cycle. Case 2: A male smoker with low sperm count. Suggestion: Quit smoking and reduce alcohol intake to improve his fertility. Case 3: A woman developed pelvic inflammatory disease (PID) after multiple sexual partners and did not use protection. Suggestion: Practice safe sex, get regular sexually transmitted infection (STI) testing, and avoid douching. 5 At the end of the lesson, encourage students to develop their critical thinking skills by answering the following questions. • What are some lifestyle factors that can positively affect the reproductive systems? Give three factors. • How does exercise affect reproductive health? ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 23 © Praxis Publishing Singapore Pte. Ltd. • Can stress negatively impact fertility? • Are there certain foods or nutrients that support reproductive health? • How does smoking or alcohol consumption affect fertility? Assessment and Evaluation 1 Assess students’ understanding of all the concepts learned by observing their participation and responses in class discussions and activities. 2 Assess students’ collaboration skills and digital skills through group discussion about lifestyle factors that support the reproductive systems. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercise 1 Workbook p. 16 . Students can get extra information on lifestyle factors that help male fertility via the QR code given. 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure • To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Lifestyle choices are habits and ways of life that can have a significant impact on fertility as well as general health and well-being. 2 Many lifestyle factors such as nutrition, exercise, sleep, oral health, stress level and others can have substantial effects on the reproductive system. 3 A healthy diet includes plenty of fruits, vegetables and whole grains. These foods are packed with nutrients that are essential for reproductive health. 4 In females, gum diseases and cavities have a negative impact on pregnancy. In males, poor oral health can reduce sperm count and sperm’s motility. 5 Exercise helps to keep the body healthy and can also improve fertility. 6 Sleep is essential for overall health and well-being, and it can also help to improve fertility and regulate hormones. 7 Smoking and excessive alcohol consumption can damage the reproductive system and increase the risk of infertility. 8 Stress can have a negative impact on overall health, and it can also affect fertility. Practice healthy ways to manage stress, such as yoga, meditation, or massage. 9 By following these lifestyle factors, it can help to improve the reproductive health and increase the chances of having a healthy pregnancy. • Ask students to reflect on what they have learned in this chapter by completing the sections ‘Recall’ Textbook p. 25 and ‘Concept Map’ Workbook p. 19 . • Let students complete the ‘Objective Questions’ Workbook pp. 17–18 and ‘Online Quick Quiz’ Workbook p. 20 to check their mastery of this chapter. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 24 © Praxis Publishing Singapore Pte. Ltd. • To reinforce students’ critical thinking skills, have them answer the questions in ‘Put on your Thinking Cap’ Textbook p. 26 and ‘HOTS Daily Application’ Workbook p. 20 that require them to analyse, evaluate or create based on the knowledge they have acquired. • Give students a preview of what will be covered in the upcoming chapter to help them get ready. Extension / Follow-up Activities Interview about Lifestyle Choices and their Effects on Reproductive Health 1 Let students work in pairs. 2 Have students interview people about their lifestyle choices and how they have affected their reproductive health. 3 Ask students to list down all the lifestyle choices on a piece of paper and analyse how these factors affect the reproductive systems. 4 Share their findings with the class. This helps in developing their communication skills. 5 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Textbook Answers Recall p. 25 1 somatic cells; reproductive cells 2 anaphase 3 two; four 4 cytoplasm 5 crossing over 6 testes; ovaries 7 semen 8 oogenesis 9 ovulation 10 uterus 11 fertile phase 12 puberty 13 Fallopian tube 14 blastocyst; foetus 15 implantation 16 amniotic fluid; umbilical cord 17 cysts 18 ovarian cancer 19 lifestyle factors ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 25 © Praxis Publishing Singapore Pte. Ltd. Put on your Thinking Cap p. 26 1 The halving of the number of chromosomes in gametes ensures that zygotes have the same number of chromosomes from one generation to the next. 2 The sperm has a streamlined body that allows it to move rapidly to reach the ovum. Its tail moves with whip-like movements to propel the sperm forwards. The mitochondria supply the energy the tail needs to move. The acrosome contains enzymes which enable the sperm to penetrate the egg. 3 The placenta provides the foetus with oxygen, nutrients and antibodies from the mother’s blood, and removes carbon dioxide and urea from the foetus. It also produces hormones that help the foetus grow. This will deprive the foetus of oxygen and nutrients and cause heavy bleeding in the mother. Project: Birth Control Methods Textbook p. 27 1 Introduction (a) Introduce the concept of fertilisation and pregnancy. (b) Tell students that birth control methods are techniques used to prevent pregnancy. There are various types of birth control methods available on the market. It is important to consult with a healthcare provider to determine which method is best suited for an individual’s needs and lifestyle. (c) Explain to students that they will carry out their own research on birth control methods such as condom and contraceptive pills using the Internet, books or other resources. (d) Set a deadline for them. 2 Research planning and execution (a) Get students into a few groups. (b) Advise them to use the Internet to find information about birth control methods. Advise them to refer to a few reliable websites, not just one. (c) Encourage them to discuss their findings and then make a comparison between the different methods of birth control. 3 Reflection and presentation (a) Instruct students to reflect on what they have learnt in the process regarding the new knowledge, the collaboration work and the improvements if they could repeat it. (b) Advise them to prepare a poster or a digital presentation to show their findings. (c) Allow them to present their findings. Encourage them to discuss the similarities and differences of their findings with other groups. 4 Assessment Assess students based on the following criteria: (a) The accuracy, clarity and completeness of the findings (b) The equally shared responsibilities and participation among the group members (c) The ability to meet the deadline (d) The effectiveness of the presentation in communicating the findings (e) The audience’s participation and engagement during the presentation ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 26 © Praxis Publishing Singapore Pte. Ltd. Reproduction in Animals and Plants CHAPTER 2 Introduction Organisms have the ability to reproduce. Reproduction is the process by which organisms produce offspring. It is essential for the survival of species, as it allows for the passing on of genetic information from one generation to the next. There are two main types of reproduction: asexual reproduction and sexual reproduction. Both animals and plants can reproduce sexually and asexually. Reproductive technologies are used in animals and plants to improve breeding, increase production, and preserve endangered species. Lessons and Learning Objectives 2.1 Sexual Reproduction in Animals • Describe the sexual reproduction of animals 2.2 Asexual Reproduction in Animals • Describe the asexual reproduction of animals 2.3 Sexual Reproduction in Flowering Plants • Describe the sexual reproduction of flowering plants • Identify the male and female reproductive parts of a flower and describe their functions 2.4 Pollination • Describe the different types of pollination • Explain the process of pollination and its importance in plant reproduction • Relate the characteristics of the flowers to their agents of pollination 2.5 The Development of Fruits and Seeds in Plants • Describe fertilisation in plants • Describe the developments of fruits and seeds in plants 2.6 Seed Dispersal • Understand the processes of seed dispersal 2.7 Germination of Seeds • Describe the physical changes of seedlings during germination 2.8 Reproduction of Ferns, Mosses and Conifers • Describe the reproduction of ferns, mosses and conifers 2.9 Asexual Reproduction in Plants • Describe the asexual reproduction of plants 2.10 The Use of Reproductive Technologies • Explain with examples, the reproductive technologies in animals and plants ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 27 © Praxis Publishing Singapore Pte. Ltd. Key Terms 2.1 sexual reproduction, asexual reproduction, offspring, internal fertilisation, external fertilisation, spawning 2.2 binary fission, budding, fragmentation, parthenogenesis, regeneration 2.3 flower, sepal, petal, stamen, anther, pollen grains, filament, carpel (or pistil), stigma, style, ovary, ovule, bisexual 2.4 pollination, self-pollination, cross-pollination, pollinating agent, pollinator 2.5 fertilisation, vegetative cell, generative cell, pollen tube, micropyle, endosperm, polar nuclei, double fertilisation, seed formation, seed, fruit, pericarp, epicarp, mesocarp, endocarp 2.6 seed dispersal 2.7 germination, dicotyledonous seeds, monocotyledonous seeds, testa, cotyledon, plumule, radicle, hilum, epigeal germination, hypogeal germination 2.8 non-flowering, fern, moss, conifer, sporangia, alternation of generations, sporophyte, gametophyte, spores, cones 2.9 vegetative reproduction, roots, stems, leaves, rhizomes, bulbs, runners, tubers, artificial vegetative reproduction, stem cutting, grafting, layering, air layering 2.10 reproductive technologies, artificial insemination, embryo transfer, in vitro fertilisation (IVF), cloning, artificial pollination, tissue culture ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 28 © Praxis Publishing Singapore Pte. Ltd. Lesson 2.1 Sexual Reproduction in Animals Learning Outcomes • Define reproduction • Describe the different types of reproduction in animals • Describe the different types of fertilisation in animals • Identify animals that reproduce by internal and external fertilisation Key Understanding Reproduction is the process by which new individuals of the same species are produced, either sexually or asexually. It is essential for the continuation of a species and involves the transfer of genetic material from one generation to the next. There are two types of reproduction, namely sexual reproduction and asexual reproduction. In sexual reproduction, offspring are produced from two parents. Asexual reproduction involves only a single parent and produces genetically identical offspring. Just like humans, almost all animals reproduce sexually. Fertilisation can occur either inside (internal fertilisation) or outside (external fertilisation) the body of the female. Induction 1 Begin by reviewing basic concepts from the previous lesson on reproduction such as gametes, ovulation and fertilisation. 2 Recall students’ memories by asking them some questions. • What are the male and female reproductive organs? • What is the role of the male and female reproductive systems in reproduction? • What is the role of sperm and eggs in reproduction? • How does fertilisation take place? 3 Explain that animals and plants also reproduce to create new offspring, just as humans do. Ask students what would happen if all the animals and plants were unable to reproduce. Teaching and Learning Activities Textbook pp. 29–31 1 Introduce that there are two types of reproduction, namely sexual reproduction and asexual reproduction. Compare both types of reproduction. 2 Show students a few examples of organisms and let students identify what type of reproduction these organisms carry out. Here are some examples of organisms. • Lion • Frog • Shark • Bacteria • Jellyfish • Potatoes with bud • Sunflower Encourage students to give more such examples. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 29 © Praxis Publishing Singapore Pte. Ltd. 3 Have students work in groups and create a presentation about the reproduction of a specific animal, either sexual or asexual. They should include information about the male and female reproductive organs, how the animal reproduces, and any interesting facts about the animal’s fertilisation and pregnancy. The students can use the Internet to gather the information. 4 Introduce the terms internal and external fertilisation. Explain that internal fertilisation occurs when the sperm fertilises the egg inside the female’s body. External fertilisation occurs when the sperm fertilises the egg outside the female’s body. 5 Using an example of animal (such as chicken), explain how it reproduces by internal fertilisation. 6 Introduce a few ways in which offspring is produced through internal fertilisation. Refer to Science Facts. 7 Using examples of animals (such as fish and frog), explain how they reproduce by external fertilisation. 8 Show students other images of animals that reproduce by internal and external fertilisation. Encourage students to give other examples. Discuss the advantages and disadvantages of each type of fertilisation. 9 Encourage students to develop their critical thinking skills by answering the questions in Think About It. 10 At the end of the lesson, encourage students to develop their critical thinking skills by answering the following questions. • What are the different ways that organisms can reproduce? • What are some examples of organisms that reproduce sexually? • What are some examples of organisms that reproduce asexually? • What is the main difference between internal and external fertilisation? • What are some advantages and disadvantages of each type of fertilisation? Give two each. • What factors can affect the success rate of external fertilisation in aquatic organisms? Assessment and Evaluation 1 Assess students’ understanding of all the concepts learned by observing their participation and responses in class discussions and activities. 2 Assess students’ critical thinking skills through their answers to the questions in Think About It and the questions at the end of the lesson. 3 Assess students’ digital skills and collaboration skills through the activity about collecting information using the Internet on the reproductive system of a specific animal. 4 Have students complete Exercises 1−4 Workbook pp. 21–22 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a quiz, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Reproduction is the process through which new offspring are generated by existing individuals or parents to ensure the survival of the species. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 30 © Praxis Publishing Singapore Pte. Ltd. 2 There are two types of reproduction: sexual reproduction and asexual reproduction. 3 Sexual reproduction is a type of reproduction in which offspring are produced from two parents. The offspring inherit genetic material from both parents, and they are not genetically identical to either parent. Sexual reproduction is common in animals and plants. 4 Asexual reproduction is a type of reproduction in which offspring are produced from a single parent. The offspring are genetically identical to the parent, and they are produced without the fusion of gametes. Internal and External Fertilisation 5 There are two types of fertilisation in animals: internal fertilisation and external fertilisation. 6 Internal fertilisation occurs when the sperm fertilises the egg inside the female’s body. This is the most common type of fertilisation in animals. 7 Internal fertilisation requires the male to insert his sperms into the female’s reproductive tract. 8 External fertilisation occurs when the sperm fertilises the egg outside the female’s body. This is less common than internal fertilisation. 9 External fertilisation usually happens in water, where the male and female release their gametes into the water at the same time. Extension / Follow-up Activities Advantages and Disadvantages of Sexual Reproduction 1 Divide students into groups. 2 Ask each group to collect information about the advantages and disadvantages of sexual reproduction and write them down on a poster. 3 Ask each group to present the outcomes of their findings. This helps in developing their communication skills. 4 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Textbook Answers Think About It p. 31 1 True 2 True 3 False 4 True 5 False Lesson 2.2 Asexual Reproduction in Animals Learning Outcomes • Identify different types of asexual reproduction in animals • Give examples of animals that reproduce asexually ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 31 © Praxis Publishing Singapore Pte. Ltd. Key Understanding Asexual reproduction is a type of reproduction in which offspring are produced from a single parent. The offspring are genetically identical to the parent, and they are not produced through the fusion of gametes. There are many different types of asexual reproduction in animals such as binary fission, budding, fragmentation and parthenogenesis. Induction 1 Guide them to wonder if an animal can reproduce without mating. 2 Ask students about what they already know about animals that reproduce asexually. Teaching and Learning Activities Textbook pp. 32–33 1 Introduce the concept of asexual reproduction. Ask students to give some examples of animals that can reproduce asexually. Examples of animals are as follows: • Bacteria • Planarians • Earthworms • Yeast • Starfish • Flatworms • Hydra • Sea cucumbers • Sponge 2 Discuss the different types of asexual reproduction. Some of the most common examples include binary fission, budding, fragmentation and parthenogenesis. 3 Introduce the concept of binary fission. Explain that binary fission is a type of asexual reproduction in which a single cell divides into two identical cells. 4 By using examples of animals (such as Amoeba and Paramecium) in the textbook, discuss the stages of binary fission. 5 Show prepared slides of bacteria undergoing binary fission under a microscope and explain the different stages of the process. Students can also watch this video by scanning the QR code below. Encourage students to ask questions and participate in a discussion about the significance of binary fission in bacterial reproduction. 6 Introduce the concept of budding. Explain that budding is a type of asexual reproduction in which a new individual develops from the bud of a parent organism. 7 Discuss the process of budding in Hydra, including the formation of a bud, its growth and development, and eventual detachment from the parent organism. 8 Let students watch a video about budding in animals by scanning the QR code below. State how to differentiate between budding and binary fission. 9 Introduce fragmentation. Explain that fragmentation is a type of asexual reproduction in which a parent organism breaks into fragments, each of which can develop independently into a new individual. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 32 © Praxis Publishing Singapore Pte. Ltd. 10 By using an example of animal (such as Planaria), discuss the steps of fragmentation. 11 Ask students to identify organisms that reproduce by fragmentation. 12 Guide students to differentiate between fragmentation and regeneration. Refer to Science Facts. 13 Define parthenogenesis as a type of asexual reproduction in which an egg develops into a new organism without being fertilised by a sperm. Ask a few students to give some examples of animals that reproduce by parthenogenesis. 14 Have students work in groups to research a specific type of asexual reproduction in animals and present their findings to the class. Textbook p. 34 15 Have students compare and contrast sexual and asexual reproduction. 16 Let students work in pairs to carry out Activity 1 to observe some animals and identify their methods of asexual reproduction. Each pair of students draws and shares their labelled diagrams with the class. 17 Encourage students to enhance their critical thinking skills by answering the questions in Think About It. 18 At the end of the lesson, encourage students to develop their critical thinking skills by answering the following questions. • Why do some animals reproduce asexually? • Can animals switch between asexual and sexual reproduction depending on environmental conditions? • How do offspring produced through asexual reproduction compare to those produced through sexual reproduction in terms of health and survival? • How does binary fission help organisms to survive and reproduce? • What are the main differences between sexual and asexual reproduction? Give three differences. Assessment and Evaluation 1 Assess students’ understanding of all the concepts learned by observing their participation and responses in class discussions and activities. 2 Assess students’ digital skills and collaboration skills through Activity 1. 3 Assess students’ critical thinking skills through their answers to the questions in Think About It and the questions at the end of the lesson. 4 Have students complete Exercises 1−3 Workbook pp. 23–24 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a quiz, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Asexual reproduction is a type of reproduction in which offspring are produced from a single parent without the fusion of gametes. The offspring are genetically identical to the parent. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 33 © Praxis Publishing Singapore Pte. Ltd. 2 There are different types of asexual reproduction in animals, including binary fission, budding, fragmentation and parthenogenesis. Binary fission 3 Binary fission is the process in which a parent cell divides into two daughter cells of almost equal size. The cell replicates its genetic material (DNA), and then divides into two parts; each daughter cell receiving one copy of the genetic material. 4 Examples of animals that reproduce by binary fission are Amoeba and Paramecium. Budding 5 Budding is a method in which a new individual develops from the bud of a parent organism. The new organism eventually breaks away from the parent and becomes independent. 6 Budding is a common form of reproduction in many organisms, including yeast and Hydra. Fragmentation 7 Fragmentation is a type of asexual reproduction in which a parent organism breaks into fragments, and each fragment can grow into a new individual. 8 This type of reproduction is common in animals such as starfish and Planaria. Parthenogenesis 9 Parthenogenesis is a type of asexual reproduction in which a female organism produces offspring without being fertilised by a male. 10 Parthenogenesis is common in some insects, such as bees and ants. Extension / Follow-up Activities Advantages and Disadvantages of Asexual Reproduction in Animals 1 Divide students into groups. 2 Ask each group to discuss about the advantages or disadvantages of asexual reproduction and write them down on a poster. 3 Ask each group to present the outcomes of their findings. This helps in developing their communication skills. 4 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Textbook Answers Think About It p. 34 1 Wasps and aphids 2 Budding 3 Two ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 34 © Praxis Publishing Singapore Pte. Ltd. Lesson 2.3 Sexual Reproduction in Flowering Plants Learning Outcomes • Identify the male and female reproductive organs of a flower • Identify the different parts of a flower • Explain the function of each part of a flower • Draw a labelled diagram of a flower • Explain the importance of flowers in the process of sexual reproduction Key Understanding Plant reproduction is the production of new offspring in plants, which can be accomplished by sexual or asexual reproduction. The flower is the basic reproductive organ of plants that produces seeds through sexual reproduction. Some flowers have both male and female reproductive parts on one single flower while other flowers have their male and female reproductive parts on separate flowers. The main parts of a flower are the sepals, petals, stamens and carpels (pistils). Stamen is the male reproductive part of the flower that consists of an anther and a filament. The carpel is the female reproductive part of a flower that consists of an ovary, a stigma and a style. In flowering plants, male and female gametes are produced in the anther and ovule, respectively. Sexual reproduction in flowering plants involves the fusion of male and female gametes to produce a zygote. Induction 1 Start by asking students if they have noticed some plants bearing flowers while some not producing flowers in their surroundings. 2 Introduce that flowering plants are plants that produce flowers and non-flowering plants are plants that do not produce flowers. 3 Ask them to think about the plants that they see in their yard, in their neighbourhood, or in the park. Guide students to give some examples of flowering plants. Ask them to share their observations with the class and share what they already know about flowering plants. Teaching and Learning Activities Textbook p. 35 1 Ask students if they know how flowering plants reproduce. 2 Explain that flowers are the reproductive organs of flowering plants, containing both male and female reproductive structures. Scan the QR code given for a video about the sexual reproduction in flowering plants. 3 Show students a fresh hibiscus flower or any suitable flowers and point out the male and female parts. Explain the parts of the flower and explain the function of each part of the flower. 4 Show students a video on how to dissect and observe a flower and have them identify the parts of the flower. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 35 © Praxis Publishing Singapore Pte. Ltd. 5 Take students outside to observe different types of flowers. Have students use magnifying glasses to look at the flowers and see the different parts of the flower. Ask one or two students to share their observations of these flowers. 6 Have students draw a labelled diagram of a flower and share their drawing with the class. Textbook p. 36 7 Discuss with students what type of flowers are bisexual or unisexual. 8 Explain the differences between bisexual and unisexual flowers. Bisexual flowers have both male and female parts. Unisexual flowers have either male or female parts. 9 Encourage students to give some examples of plants as follows: • Plants that have both the male and female parts in a single flower. • Plants that have both the male and female parts in separate flowers on the same plant. • Plants that have male and female flowers on different plants. Let students share their suggestions of plants in class. 10 Get a male and a female papaya flower and have students identify the parts of the flower. Guide them to identify the male and female parts of the flower. Textbook p. 37 11 Guide students to identify sepals and petals on a flower and explain their functions. 12 Explain the difference between sepals and petals. Sepals are the green, leaf-like structures that protect the flower bud. Petals are the colourful, showy structures that attract pollinators. 13 Give students a flower with colourful petals and a flower with small, white petals. Let them think about which flower is more attractive to pollinators. 14 Have students carry out Activity 2. Observe flowers from some plants and answer the questions given. Have a class discussion based on the questions provided. 15 Encourage students to answer the questions in Think About It to get them to enhance critical thinking skills. Guide students to answer more challenging questions. • Why do you think flowers have different colours? • Why do you think flowers have different shapes? • Why do you think flowers have different scents? • What are some of the challenges that flowers face? 16 At the end of the lesson, tell students that a series of events will occur in order for reproduction in flowering plants to take place. They will learn about these processes in the following subtopics. Pollination ➞ fertilisation ➞ seed dispersal ➞ germination Assessment and Evaluation 1 Assess students’ understanding of all the concepts learned by observing their participation and responses in class discussions and activities. 2 Assess students’ digital skills and collaboration skills through Activity 2. 3 Assess students’ critical thinking skills through their answers to the questions in Think About It and the questions at the end of the lesson. 4 Have students complete Exercises 1−3 Workbook pp. 24–25 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 36 © Praxis Publishing Singapore Pte. Ltd. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Sexual reproduction in flowering plants involves the transfer of male gametes to female gametes. 2 Flowers are the sexual reproductive organs of plants. Parts of a Flower 3 The stamen is the male reproductive part of a flower. It consists of an anther and a filament. The anther produces pollen grains, which contain male gametes called sperms. The filament supports the anther and holds it up. 4 The pistil is the female reproductive part of a flower. It consists of a stigma, a style and an ovary. 5 The stigma receives pollen grains. 6 The style supports the stigma and connects it to the ovary. 7 The ovary contains ovules, which contain female gametes called ova. 8 The sepals are the outermost parts of a flower. They are usually small, green and leaf-like. They protect the flower bud while it is still developing. 9 The petals are the colourful parts of a flower. They attract pollinating insects, such as bees and butterflies, to the flower. Types of Flowers 10 A bisexual flower is one that contains both male and female reproductive parts. They are found in a wide variety of plants, including roses, tulips and sunflowers. 11 A unisexual flower is the flower that has only male or female reproductive parts. Extension / Follow-up Activities Hands-on Activity to Create a Model of a Flower 1 Divide students into groups and each group is assigned a different type of flower to create. 2 Guide students to research different types of flowers and learn about their unique characteristics before they begin creating their models. 3 Have students use a variety of materials such as coloured paper, glue, scissors and markers to create a model of a flower. The students can also decorate the flower with yarn, beads or other materials if desired. 4 Ask students to present their models to the class and explain the different parts of the flower and how they function. This helps in developing their communication skills. Encourage other students to think critically and to raise questions. 5 Let students use their models to create a flower garden in the classroom. Textbook Answers Think About It p. 37 1 Sepal 2 The petals are brightly coloured and scented. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 37 © Praxis Publishing Singapore Pte. Ltd. Lesson 2.4 Pollination Learning Outcomes • Define pollination • Identify the different types of pollination • Compare and contrast self-pollination and cross-pollination • Identify different types of pollinating agents and their role in pollination • Explain the process of pollination and its importance in plant reproduction • Relate the characteristics of the flowers to their agents of pollination • Compare the characteristics of insect-pollinated and wind-pollinated flowers Key Understanding Pollination is an essential part of plant reproduction. The transfer of mature pollen grains from the anther to the stigma of a flower is called pollination. This process helps the plant to reproduce and produce seeds. There are two main types of pollination, namely self-pollination and cross-pollination. Wind, water and animals such as insects are the agents for pollination in different plants. Induction 1 Ask students if they observe insects such as bees and butterflies going from flower to another in a garden. 2 Guide students to understand how these insects help in the reproduction of flowering plants. When a bee visits a flower, the pollen grains stick to its body. As the bee moves from flower to flower, it transfers the pollen grains. 3 Introduce to students that this process is called pollination. Teaching and Learning Activities Textbook p. 38 1 Explain what pollination is and give its definition. 2 Guide students to think about why flowering plants need to carry out pollination. Tell students that without pollination, plants would not be able to reproduce. 3 Introduce to students the two types of pollination, namely self-pollination and cross-pollination. 4 Watch the video by scanning the QR code below to understand more about self-pollination and crosspollination. 5 Guide students to compare self-pollination and cross-pollination. Textbook p. 39 6 Ask students about what they know about pollen grains. Show students pictures of several pollen grains in various sizes and shapes. 7 Ask students if pollen grains can travel and reach the stigma of the flower by themselves. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 38 © Praxis Publishing Singapore Pte. Ltd. 8 Explain that pollen grains cannot move on their own and need some external agents to transfer them to the stigma. 9 Explain how pollinating agents help plants reproduce. Explain that when a pollinating agent transfers pollen grains from one flower to another, it helps to fertilise the flower. 10 Introduce the different types of pollinating agents. Explain that the common pollinating agents are insects, birds and bats. Other pollinating agents include wind and water. Explain how each type of pollinating agent helps to pollinate flowers. 11 Explain that pollination by wind that is used by many plants to transfer pollen grains through the air. 12 Show students some pictures of wind-pollinated plants such as grasses, wheats and weeds. 13 Guide students to describe the characteristics of wind-pollinated flowers that are adapted to wind pollination. 14 Demonstrate on how wind pollination works. Do this by blowing on a flower or by using a fan. Textbook pp. 40–42 15 Ask students to observe the behaviour of bees or butterflies as they collect nectar from flowers. Explain their role as pollinators when they transfer pollen grains from a flower to another. 16 Encourage students to give more examples of pollinators. Moths, wasps, birds and even bats can all be pollinators. Ask one or two volunteers to share how these pollinators help in pollination. 17 Explain the process of pollination by animals in detail by referring to page 41. 18 Ask students to compare the characteristics of insect-pollinated flowers and wind-pollinated flowers. 19 Let students carry out Activity 3 to discuss in groups to compare the characteristics of insect-pollinated flowers and wind-pollinated flowers. Answer the questions provided. 20 Explain that pollination by water is used by aquatic plants to transfer pollen grains through the help of water. 21 Ask students to give some examples of water-pollinated plants such as waterweeds, pondweeds and water hyacinth. 22 Guide students to describe the characteristics of flowers pollinated by water. 23 Let students do the following activity about pollination by different types of pollinating agents. • Divide students into groups. • Give each group a wind-pollinated flower, an insect-pollinated flower or a water-pollinated flower, but the students don’t know what type of flower they have. • Have students observe the flowers. Based on the characteristics of the flower, determine what type of pollinating agent is used to transfer pollen grains. • Have each group explain how the given flower is pollinated. • Have students draw a diagram of the flower and label its parts. Share their diagrams with the class. 24 At the end of the lesson, encourage students to develop their critical thinking skills by answering the following questions. • What is pollinating agent? • What are some examples of pollinating agents? Give three examples. • What are some examples of insect-pollinated flowers? Give three examples. • How do wind-pollinated plants differ from insect-pollinated plants? Give two. • Why do wind-pollinated flowers produce so much pollen grains? • What are the characteristics of water-pollinated flowers? Give two. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 39 © Praxis Publishing Singapore Pte. Ltd. Assessment and Evaluation 1 Assess students’ understanding of pollination through their participation in class discussions. 2 Assess students’ collaboration skills through observation of their participation during Activity 3 and review their answers based on the questions given and discussions. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1−5 Workbook pp. 25–27 . Students can get extra information on pollination via the QR code given. 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Pollination is the transfer of mature pollen grains from the anther to the stigma of a flower. 2 There are two types of pollination, namely self-pollination and cross-pollination. 3 Self-pollination is the transfer of pollen grains from the anther to the stigma of the same flower, or from the anther to the stigma of another flower on the same plant. 4 Cross-pollination is the transfer of pollen grains from the anther of one plant to the stigma in a flower of another plant of the same species. Pollinating Agents 5 Pollen is a fine powder produced by the male part of a flower. 6 A pollinating agent is needed for the transfer of pollen grains from the male part of a flower to the female part. The agents include wind, water and animals such as insects. 7 Wind pollination is a common method of pollination for plants that grow in open areas, such as grasses, wheats and weeds. 8 Wind-pollinated plants typically have small, inconspicuous flowers that produce large amounts of pollen grains. 9 The pollen grains of wind-pollinated plants are typically small and lightweight, which allows them to be easily carried by the wind. 10 Animals that pollinate flowers include bees, butterflies, bats, hummingbirds and flies. 11 Animals are attracted to flowers by their bright colours, sweet smells and nectar. 12 When an animal lands on a flower, it may brush against the male part of the flower and pick up pollen grains. The animal then carries the pollen grains to another flower, where it may fertilise the female part of the flower. 13 Water pollination is rare and is only found in a small number of aquatic plants. 14 Water-pollinated plants typically have flowers that are buoyant or that float on the surface of the water. 15 The pollen grains of water-pollinated plants are typically small and lightweight, which allows them to be easily carried by the water. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 40 © Praxis Publishing Singapore Pte. Ltd. Extension / Follow-up Activities Pollinators and the Environment 1 Divide students into groups of four. 2 Discuss in groups about the importance of pollinators to the environment. 3 Have students brainstorm ways to help protect pollinators. Let each group of students prepare a presentation on the importance of pollinators and ways to protect them. 4 Ask each group to give their presentation. This helps in developing their communication skills. 5 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Textbook Answers Activity 3 p. 42 2 Chrysanthemums have bright colours, a strong fragrance, and attract insects like bees and butterflies for pollination. Barley flowers are small, lack vibrant colours or strong fragrances, and are likely pollinated by wind due to their lightweight pollen grains. Lesson 2.5 The Development of Fruits and Seeds in Plants Learning Outcomes • Explain the process of fertilisation in plants • Describe the formation of fruits and seeds • Identify the structures involved in pollen tube formation • Describe the process of double fertilisation and explain how it results in the formation of a seed • Describe the structure of a seed, including the seed coat, embryo and endosperm • Identify the different parts of a fruit, including the pericarp Key Understanding Fertilisation takes place after pollination. During fertilisation, the male gametes from the pollen grains fuse with the female gametes in the ovules to form a zygote. The fertilised egg cell develops into an embryo, which is the beginning of a new plant. The endosperm provides food for the embryo to grow. The ovary of the flower develops into a fruit, which surrounds and protects the seed. The pericarp is the wall of the fruit that develops from the ovary of the flower. It is made up of three layers: the epicarp, the mesocarp and the endocarp. Some fruits have many seeds and some have a single seed. Induction 1 Begin by asking students what they know about fertilisation. 2 Explain that fertilisation will take place after a flower is pollinated. Teaching and Learning Activities Textbook pp. 43–44 1 Describe the steps that occur after the pollen grains land on the stigma of a flower. • Using the figure in the textbook, demonstrate how the pollen grain germinates and forms a pollen tube that grows down through the style and into the ovary. • Explain the role of two sperm cells contained in the pollen grains. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 41 © Praxis Publishing Singapore Pte. Ltd. 2 Introduce what double fertilisation is and explain how it occurs to form a zygote and an endosperm. 3 Watch this animation to learn how double fertilisation occurs in flowering plants by scanning the QR code below. 4 Explain that when a fertilised egg cell is formed, it begins to develop into a seed. The seed contains an embryo, an endosperm and a protective coat. Ask students to give functions of these structures of the seed. 5 Explain that the ovary of the flower develops into a fruit. Guide students to describe the functions of the fruit. Textbook p. 45 6 Introduce the definition of pericarp. Discuss the definition with students. 7 Explain the three layers of pericarp: epicarp, mesocarp and endocarp. Discuss the function of each layer with students. 8 Guide students to give examples of fruits that have many seeds and fruits that have one seed. Discuss the fruits with students. 9 Explain why some fruits have many seeds and others have one seed. 10 Let students work in pairs and each pair brings a fresh fruit. Let them dissect the fruit. Have students identify the three layers of pericarp and the seeds in the fruit. Discuss the results of the dissection with students. 11 Have students carry out Activity 4 to find out the different types of fruits. Share their findings with the class. 12 Organise a field trip to a local farm or botanical garden where students can observe the various stages of seed and fruit development in different plant species. (If time permits) 13 Ask students some questions to start a class discussion. Randomly select a few students to share their answers. • How does a pollen tube form? • Why is double fertilisation necessary for the production of seeds? • What are the two products of double fertilisation? • What is the function of the endosperm in a seed? • What are some examples of fruits with a fleshy pericarp? • Why do some fruits have more seeds than others? Assessment and Evaluation 1 Assess students’ understanding of the development of fruits and seeds in plants through their participation in class discussions. 2 Assess students’ digital skills and collaboration skills through Activity 4. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1−4 Workbook pp. 28–29 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 42 © Praxis Publishing Singapore Pte. Ltd. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. The Development of Fruits and Seeds in Plants 1 In flowering plants, the male gametes are contained in pollen grains, and the female gametes are contained in ovules. Fertilisation is the fusion of male and female gametes to form a zygote. 2 Once a pollen grain lands on the stigma of a flower, it germinates and grows a pollen tube. 3 The pollen tube grows down the style of the flower and into the ovary. 4 Inside the ovary, the pollen tube releases two sperm cells. 5 Double fertilisation is a process that occurs in flowering plants. It involves the fusion of two sperm cells with two different types of female gametes, resulting in the formation of a zygote and an endosperm. 6 One sperm cell fertilises the egg cell, which forms a zygote. 7 The other sperm cell fertilises two polar nuclei, which forms an endosperm. 8 The zygote develops into an embryo, which is the beginning of a new plant. 9 The endosperm provides food for the embryo to grow. 10 Once the embryo is fully developed, the ovary develops into a fruit. Fruits 11 The fruit protects the seed and helps it to disperse. 12 The pericarp is the outermost layer of a fruit. It is made up of three layers: the epicarp, the mesocarp and the endocarp. 13 The epicarp is the outermost layer of the pericarp. It is the skin of the fruit. The epicarp can be thin or thick, and it can be smooth or rough. 14 The mesocarp is the middle layer of the pericarp. It is the flesh of the fruit. The mesocarp can be fleshy or dry, and it can be sweet or sour. 15 The endocarp is the innermost layer of the pericarp. It is the layer that surrounds the seeds. The endocarp can be hard or soft, and it can be smooth or rough. 16 Some fruits, such as apples and oranges, have many seeds. Other fruits, such as cherries and plums, have a single seed. Extension / Follow-up Activities Different Types of Fruits that are Used for Food 1 Divide students into groups. 2 Ask each group to research the different types of fruits that are used for food using the Internet and prepare a presentation to show the photos of fruits and their functions. 3 Ask each group to present the outcomes of their findings. This helps in developing their communication skills. 4 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 43 © Praxis Publishing Singapore Pte. Ltd. Lesson 2.6 Seed Dispersal Learning Outcomes • Explain the importance of seed dispersal in plant reproduction • Describe the methods of dispersal of seeds and fruits and their characteristics • Differentiate between the different methods of seed dispersal • Explain the benefits of seed dispersal for plants Key Understanding Seed dispersal is the movement of seeds away from the parent plant. Seed dispersal is important for plant reproduction. It helps to ensure that the seeds are dispersed to a new location, where they can grow into new plants and avoid competition with other plants. There are several methods of seed dispersal, including wind, water, animals and explosions. Each method has its own advantages and disadvantages. Induction 1 Show students two pictures of seedlings in two containers. • A lot of seedlings grow in the overcrowded container. • One seedling grows in another container. 2 Ask students some questions to start a discussion in the class. • Which container of seedlings do you think will grow well and healthy? • Why do you think so? • What are the benefits of having enough space for seedlings to grow? • What are the drawbacks of overcrowding of seedlings? Teaching and Learning Activities Textbook p. 46 1 Introduce the term seed dispersal. 2 Explain why it is important for seeds and fruits to be dispersed. 3 Explain that seed dispersal is the movement of seeds away from the parent plant. 4 Discuss the different ways that seeds can be dispersed. This process can happen in a variety of ways, including by wind, water, animals or explosion. 5 Explain to students that wind dispersal is the movement of seeds by the wind. 6 Ask students to identify plants that disperse their seeds by wind. 7 Discuss the different ways that wind dispersal can help plants reproduce. Some examples include: • Wind can carry seeds over long distances, which helps plants to colonise new areas. • Wind can help to distribute seeds evenly, which helps to prevent overcrowding. • Wind can help to break up the seeds, which helps them to germinate. 8 Ask students to carry out an activity called seed balloon launch. They can attach seeds to balloons and release them into the air, tracking their dispersal patterns. Textbook p. 47 9 Explain to students that animals can disperse seeds and fruits in a number of ways. • Some animals eat the seeds and then pass them through their digestive system, which helps to break down the seed coat and makes it easier for the seed to germinate. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 44 © Praxis Publishing Singapore Pte. Ltd. • Other animals carry seeds in their fur or feathers, which can help to transport the seeds to new locations. 10 Explain the modified structure of a seed that is suited to dispersal by animals. 11 Explain to students that water dispersal is a method where seeds are dispersed by water. 12 Show students pictures of different seeds. Ask students to identify the seeds and to describe how they might be dispersed by water. Describe the characteristics of these seeds. 13 Explain to students that water can disperse seeds in a number of ways. • Some seeds float on the surface of the water and can be carried over long distances by currents. • Other seeds are attached to fruits that float on the water. • Other seeds are eaten by aquatic animals, and the seeds are then deposited in new locations when the animals defecate. Textbook p. 48 14 Explain to students that explosive seed dispersal is a method where the seeds are dispersed by the force of an explosion. 15 Show students pictures of different plants that disperse their seeds by explosion. Ask students to name the plants and to describe how they disperse their seeds. 16 Guide students to describe how plants benefit from seed dispersal. 17 Ask students to carry out Activity 5. Share their findings in the class. 18 Ask students to answer some questions to enhance their critical thinking skills. • How does wind affect the dispersal of seeds? • Why do wind-dispersed seeds have to be lightweight? • What are some characteristics that plants have for water dispersal? • What are some examples of animals that disperse seeds? • What are some examples of structures that aid in dispersal by explosion? Assessment and Evaluation 1 Assess students’ understanding of seed dispersal through their participation in class discussions. 2 Assess students’ digital and collaboration skills through Activity 5. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1−4 Workbook pp. 30–31 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Seed dispersal is the process by which seeds are spread or transported away from their parent plant to a new location where they can germinate and grow. 2 There are several methods of seed dispersal, including wind, water, animals and explosion. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 45 © Praxis Publishing Singapore Pte. Ltd. 3 Wind is the most common type of seed dispersal. Seeds that are dispersed by wind are often light and have wings or other structures that help them to catch the wind. 4 Water can also disperse seeds. Seeds that are dispersed by water are often buoyant or have structures that help them to float. 5 Animals can also disperse seeds. Seeds that are dispersed by animals are often eaten by the animal and then deposited in a new location in the animal’s droppings. 6 Some seeds are released from the plant by a force of explosion. This allows the seeds to be dispersed over a wide area. Extension / Follow-up Activities Different Types of Seeds for Dispersal 1 Divide students into groups. 2 Have students collect seeds from plants that disperse their seeds by different types of dispersal methods. 3 Have students observe the seeds that they collect and identify the different ways that they are adapted to each type of dispersal. 4 Prepare a presentation to show the photos of seeds and their dispersal methods. 5 Ask each group to present the outcomes of their findings. This helps in developing their digital and communication skills. 6 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Lesson 2.7 Germination of Seeds Learning Outcomes • Identify the structure of a seed and their functions • Define germination and describe the process • Describe the different types of seed germination • Identify the conditions required for germination of seeds • Explain the importance of germination for plant reproduction • Carry out an experiment to study the conditions required for germination of seeds Key Understanding A seed is a structure that encloses the embryo of a plant in a protective outer covering called testa or seed coat. Seeds remain dormant until conditions are favourable for germination. Germination is the process of seeds developing into new plants. There are two types of seed germination: epigeal germination and hypogeal germination. All seeds need water, oxygen and suitable temperature to germinate. Induction 1 Begin by asking students to share what they know about seeds. 2 Ask students some questions to start a class discussion. • What are seeds? • Where do they come from? • How do they grow into plants? ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 46 © Praxis Publishing Singapore Pte. Ltd. Teaching and Learning Activities Textbook p. 49 1 Get a mung bean and a maize grain. Discuss the structures of both seeds. 2 Describe the structure of a seed using a labelled figure. Explain the function of each part of the seed. 3 Show students a germinated seed or a seedling and have them examine them with magnifying glasses. Help them to identify the different parts of a seed, such as the plumule, radicle and cotyledon. Textbook pp. 50–51 4 Introduce the term “germination”. 5 Ask a volunteer to give the definition of germination. Discuss with students to give a more accurate definition of germination. 6 Watch an animation about germination of seeds by scanning the QR code below. 7 Explain the process of germination of seeds using a flow map. Refer to page 50. 8 Show a time-lapse video of seed germination and have students identify the different parts of the plant as they emerge. This activity can help students understand the importance of seeds in plants. 9 Have students plant their own seeds in small cups or pots and observe the process of germination. Ask students to record their observations in a journal or on a chart, noting changes in the seed’s appearance and growth over time. This hands-on approach can help students understand the process of germination and the factors that contribute to successful growth. 10 Explain to students the different types of seed germination. Discuss the differences between epigeal germination and hypogeal germination. To compare them, watch this video by scanning the QR code below. Textbook pp. 51–52 11 Guide students to identify the conditions required for seed germination. Seeds need water, oxygen and suitable temperature to germinate. 12 Ask students to carry out Experiment 1 and guide them to study the conditions required for the germination of seeds. 13 At the end of the lesson, encourage students to develop their critical thinking skills by answering the following questions. • What is the outermost layer of a seed called and what is its function? • What role do the cotyledons play in the germination process? • What are the three main factors that affect seed germination? ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 47 © Praxis Publishing Singapore Pte. Ltd. • What is the ideal temperature range for seed germination? • Can seeds still germinate after being stored for a long time? Assessment and Evaluation 1 Assess students’ understanding of the germination of seeds through their participation and responses in class discussions and activities. 2 Assess students’ science process skills through Experiment 1. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1−7 Workbook pp. 31–33 . Students can get extra information on seed germination via the QR code given. 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. Structures of a Seed and their Functions 1 The seed absorbs water and air through a small opening called micropyle. 2 The water softens the testa and the seed swells. 3 The testa ruptures and the radicle grows downwards into the soil to form the root. 4 The plumule grows upwards to form the shoot. 5 The cotyledons shrink and fall off. 6 The seedling starts to carry out photosynthesis. Germination 7 Germination is the process by which a seed begins to grow into a new plant. 8 There are two types of seed germination: epigeal germination and hypogeal germination. 9 During epigeal germination, the cotyledons are brought above the ground due to the elongation of the hypocotyl. 10 During hypogeal germination, the cotyledons of seeds remain below the soil surface. 11 When there is sufficient water, suitable temperature and adequate supply of oxygen, seeds will germinate and develop into new plants. 12 Seeds need water to germinate. Water is needed to soften the testa and to activate the enzymes. The activated enzymes break down the stored starch in the cotyledon to glucose which can then be used in respiration to provide energy for growth. 13 Seeds need a certain temperature range to germinate. A suitable temperature is needed to activate the enzymes. Many seeds germinate at temperatures ranging from 10ºC to 35ºC. 14 Seeds need oxygen to germinate. Oxygen in air is needed for cell respiration to provide energy for growth. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 48 © Praxis Publishing Singapore Pte. Ltd. Extension / Follow-up Activities Germination of a Specific Type of Seed 1 Divide students into groups. 2 Have students research a specific type of seed and describe how this seed germinates. 3 Get students to germinate the seed and identify the conditions needed for its germination. Write down the findings on a poster. 4 Ask each group to present the outcomes of their findings. This helps in developing their digital and communication skills. 5 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Textbook Answers Experiment 1 p. 52 Observations: Boiling tube Conditions in the boiling tubes Seed germination Water Air Suitable temperature A 3 3 3 Seeds germinate. B 7 3 3 Seeds do not germinate. C 3 7 3 Seeds do not germinate. D 3 3 7 Seeds do not germinate. Discussion: 1 Boiling tube A serves as the control in this experiment. 2 The seeds in boiling tube B do not germinate because water is not present. The seeds in boiling tube C do not germinate because there is no air in the boiled water. The seeds in boiling tube D do not germinate because the temperature is too low. 3 A layer of oil in boiling tube C prevents air from entering the boiled water. 4 The seeds will germinate as light is not necessary for germination. Conclusion: The hypothesis is accepted. Seeds need water, air and suitable temperature (warmth) for germination. Lesson 2.8 Reproduction of Ferns, Mosses and Conifers Learning Outcomes • Identify and describe the characteristics of non-flowering plants, such as ferns, mosses and conifers • Explain how non-flowering plants reproduce • Explain the concept of alternation of generations in non-flowering plants ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 49 © Praxis Publishing Singapore Pte. Ltd. Key Understanding Non-flowering plants are a group of plants that do not produce flowers. They reproduce by spores or seeds. Examples of non-flowering plants include ferns, mosses and conifers. Ferns reproduce through spores, which are released from the underside of their fronds. These spores develop into tiny plants called gametophytes, which produce both male and female reproductive cells. Mosses also reproduce through spores, which are released from the tips of their stalks. The spores develop into small plants, which eventually grow into mature moss plants that produce both male and female reproductive structures. Conifers reproduce through the production of seeds that are typically contained within cones. The male cones produce pollen grains that fertilise the female cones, leading to the development of seeds. The seeds produced by conifers can be dispersed by wind or animals and can remain dormant for long periods before germinating under favourable conditions. Induction 1 Begin by asking students to share what they already know about non-flowering plants. 2 Encourage students to discuss the following questions: • What are non-flowering plants? • What are some examples of non-flowering plants? • Can non-flowering plants reproduce sexually? 3 Explain that non-flowering plants are plants that do not produce flowers. These plants reproduce in a variety of ways. For example, mosses and ferns reproduce by spores while conifers reproduce by cones. Teaching and Learning Activities Textbook pp. 53–54 1 Show students a fern plant. Let students observe the fern plant and examine it with magnifying glasses. 2 Have students examine fern fronds and identify structures such as sori, which contain sporangia that produce spores. 3 Explain to students how fern plants reproduce by spores. Explain how the spores are released and dispersed, and how they require moisture to germinate and grow into new fern plants. 4 Discuss the unique life cycle of ferns, including their alternation of generations between a haploid gametophyte and a diploid sporophyte. 5 Prepare a wet mount slide by placing a small drop of water on a clean glass slide. Place the spores on the water droplet and cover it with a coverslip. Use the microscope to observe the spores in terms of shape, size and colour. Textbook pp. 54–56 6 Take students on a moss hunt. Find different types of mosses growing in the schoolyard, park or other nearby area. Moss is typically found in moist, shady environments. 7 Bring the moss samples back to the classroom and examine them with magnifying glasses. Help students identify the different parts of the moss plant, such as the capsule, stalk, leaves and rhizoid. 8 Explain the life cycle of moss to students. Show them how the moss plant reproduces both sexually and asexually. 9 Explain how the life cycle of moss follows the pattern of alternation of generations. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 50 © Praxis Publishing Singapore Pte. Ltd. 10 Have students create their own terrariums for moss. Fill a shallow tray with potting soil and add some small stones, shells, or other decorations. Gently place the moss samples in the terrarium and spray them with water. 11 Place the terrariums in a sunny spot and water them regularly. Observe the moss over time and see how it grows. Textbook pp. 57–59 12 Show students pictures of conifer trees. Ask them to identify the characteristics of these trees. Conifers have needles instead of leaves, they have cones, and they are evergreen. 13 Show students a pinecone. Ask them to describe what they see. Pinecones have scales, and they contain seeds. 14 Discuss the life cycle of a conifer. Explain that conifers start their life as seeds. 15 Explain how conifers reproduce. Conifers produce male and female cones. 16 Introduce two types of plants: angiosperms and gymnosperms that produce seeds as a means of reproduction. Refer to Science Facts. 17 Let students complete Activity 6. Let them compare the reproduction of flowering plants and ferns. 18 At the end of the lesson, encourage students to develop their critical thinking skills by answering the following questions. • Can ferns, mosses and conifers reproduce sexually and asexually? • How do ferns reproduce? • What is the structure that ferns produce spores? • What is the ideal habitat for moss? • What is the haploid generation in the life cycle of moss? • Which structure produces male gametes in conifers? Assessment and Evaluation 1 Assess students’ understanding of all the concepts learned by observing their participation and responses in class discussions and activities. 2 Assess students’ collaboration skills and digital skills through Activity 6. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1–5 Workbook pp. 33–36 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Non-flowering plants are plants that do not produce flowers. They reproduce by spores or seeds. Ferns 2 Ferns consist of stems, leaves and roots. They have underground stems called rhizomes. The fronds grow up from the rhizome. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 51 © Praxis Publishing Singapore Pte. Ltd. 3 Sori are the reproductive structures of a fern. They are small, brown spots that are found on the underside of the fronds. Sori contains spores, which are the reproductive units of ferns. 4 The life cycle of a fern is called alternation of generations. There are two main stages in the life cycle of a fern: the haploid gametophyte stage and the diploid sporophyte stage. 5 Spore-producing non-flowering plants, such as ferns and mosses, produce spores that are carried by the wind to new locations. 6 When a spore lands in a suitable environment, it germinates and grows into a small, heart-shaped plant called gametophyte. 7 The gametophyte produces male and female gametes, which fuse to form a zygote. The zygote develops into a new fern or moss plant. Mosses 8 Mosses are small plants that grow in shady and damp areas. 9 Mosses are bryophytes that may reproduce both sexually by gametes and asexually by spores. 10 The life cycle of moss follows the pattern of alternation of generations. 11 When the spores have matured, the sporangium releases the spores into the air. 12 When they fall to the ground with suitable conditions, the spore germinates and grows into a young leafy gametophyte. 13 The gametophyte produces eggs and sperms. A sperm fertilises an egg, producing a zygote, which then develops into a sporophyte. The sporophyte grows and the spores are formed inside the capsule when it matures. Conifers 14 Conifers are seed plants. They reproduce using cones. Conifers produce both male and female cones on the same plant. 15 They bear their seeds naked which means they are not enclosed in a fruit. This type of plant is also called a gymnosperm. 16 The life cycle of a gymnosperm also involves alternation of generations. 17 The male cones produce pollen grains, and the female cones produce ovules. When a pollen grain lands on an ovule, it fertilises the ovule to produce a zygote. The zygote grows into an embryo in a seed. The seed begins to develop. 18 When the seed is mature, it falls to the ground and can germinate and grow into a young sporophyte. It then develops into a mature tree. Extension / Follow-up Activities Comparison between Non-flowering Plants and Flowering Plants 1 Divide students into groups. 2 Have students choose and compare a type of non-flowering plant and a type of flowering plant. 3 Get students to collect information about both types of plants and prepare a comparison table to compare them. 4 Ask each group to present the outcomes of their findings. This helps in developing their digital and communication skills. 5 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 52 © Praxis Publishing Singapore Pte. Ltd. Lesson 2.9 Asexual Reproduction in Plants Learning Outcomes • Identify and describe the different methods of asexual reproduction in plants • Explain the advantages and disadvantages of asexual reproduction in plants • Apply the knowledge of asexual reproduction in plants to real-world situations • Identify and describe different methods of artificial vegetative reproduction Key Understanding Asexual reproduction is a type of reproduction in which offspring are produced from a single parent without the involvement of gametes. Asexual reproduction in plants occurs through spore formation and vegetative reproduction. Vegetative propagation is a way in which a new plant is grown from a part of the parent plant, such as a stem, leaf or root. The new plant is genetically identical to the parent plant. Types of stems that plants can reproduce include rhizomes, bulbs, tubers and runners. Induction 1 Ask students what they already know about asexual reproduction. 2 Define asexual reproduction as a type of reproduction in which offspring are produced from a single parent. Explain that asexual reproduction does not involve the fusion of gametes, as sexual reproduction does. Teaching and Learning Activities Textbook pp. 59–61 1 Introduce different types of asexual reproduction in plants such as spore formation and vegetative reproduction. 2 Ask students to identify some plants that can reproduce by spores. Examples are ferns, mosses and algae. Explain how plants use spores to reproduce. 3 Define vegetative reproduction in plants as a type of reproduction in which offspring are produced from a part of the parent plant. 4 Have students give examples of vegetative reproduction in plants. Some examples include: • By roots: Some plants, such as sweet potatoes, can produce new plants from their roots. • By stems: Some plants, such as strawberries, can produce new plants from their stems. • By leaves: Some plants, such as begonias, can produce new plants from their leaves. 5 Explain how plants reproduce from a rhizome using an example of plant. 6 Explain how onions reproduce from a bulb. 7 Explain the advantages and disadvantages of vegetative reproduction in plants. 8 Have students apply their knowledge of asexual reproduction in plants to real-world situations. Textbook p. 62 9 Introduce that a sweet potato is a root while a potato is a stem. Learn how to distinguish between roots and modified stems. Refer to Science Facts. 10 Introduce what artificial vegetative reproduction is. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 53 © Praxis Publishing Singapore Pte. Ltd. 11 Guide students to identify some common methods of artificial vegetative reproduction such as stem cutting, grafting, layering and air layering. Explain that these methods are a quick and easy way to propagate plants. 12 Explain how a plant is propagated through stem cutting. Explain the steps involved in stem cutting. 13 Ask students to give some examples of plants that can be propagated through stem cutting. 14 Define grafting as a type of asexual reproduction in which new plants are produced by joining two parts (scion and stock) of different plants. 15 Explain that grafting is used to propagate plants that are difficult to grow from seeds or that are not able to reproduce sexually. Give some examples of plants. 16 Ask students to identify the two common types of layering such as simple layering and air layering. 17 Introduce the concept of layering to students. Explain that layering is a method of plant propagation that involves encouraging a branch to produce roots while still being attached to the parent plant. 18 Introduce the method of air layering to students. Identify the materials needed for air layering. 19 Let students work in groups to research further on the other types of methods of asexual reproduction in plants using the Internet. Share their findings to the class. 20 At the end of the lesson, ask students to answer some questions to test their understanding about asexual reproduction in plants. • What are the different types of asexual reproduction in plants? • What are some examples of plants that reproduce asexually? Give three examples. • What are the advantages of asexual reproduction in plants? • How does vegetative reproduction differ from sexual reproduction? • Can plants that reproduce vegetatively also reproduce sexually? • What are some examples of plants that reproduce through runners? Give two examples. • Which plants are best suited for using runners? Assessment and Evaluation 1 Assess students’ understanding of asexual reproduction in plants through their participation and responses in class discussions and activities. 2 Assess students’ digital skills and collaboration skills through the activity to search for other types of asexual reproduction in plants. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1−6 Workbook pp. 36–38 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a quiz, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Asexual reproduction is a type of reproduction in which offspring are produced from a single parent without the fusion of gametes. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 54 © Praxis Publishing Singapore Pte. Ltd. 2 In plants, asexual reproduction can occur in a variety of ways, including spore formation and vegetative reproduction. Vegetative Reproduction 3 Vegetative reproduction is a type of asexual reproduction in plants that involves the growth of new plants from parts of the parent plant, such as roots, stems or leaves. It is a common and efficient way to propagate plants, and it can be used to produce new plants that are genetically identical to the parent plant. 4 Some plants, such as sweet potato, have swollen roots that function as storage structures. Buds are formed at the base of the stem and can be used to grow new plants. 5 Some plants can produce new plants from leaves. This type of reproduction is common in plants such as Bryophyllum and Begonia. In Bryophyllum, for example, small plantlets can form from buds that develop along the edges of the leaves. These plantlets can then fall off the parent plant and grow roots in moist soil. 6 Some plants have buds on their stems. The different types of stems that can reproduce include rhizomes, bulbs, tubers and runners. 7 Rhizomes are underground stems that grow horizontally. They can produce new plants from their nodes, which are the points where leaves or roots emerge from the stem. 8 Bulbs are modified stems that are used for reproduction and for storing food. In the case of onions, the new plant is produced from the bulb. 9 Runners in a plant are long stems that grow along the surface of the ground. When adventitious roots form at the nodes and buds on the runner develop into new shoots, separate plants are produced. 10 Stem tubers are swollen roots that store food. They can produce new plants from their eyes or buds. Artificial Vegetative Reproduction 11 Artificial vegetative reproduction is a type of plant reproduction that involves human intervention. 12 Stem cuttings are pieces of stem that are taken from a parent plant and rooted in a moist soil. After some time, adventitious roots develop from the stem, and a new plant starts to grow. 13 Grafting is a method in which part of the stem (called scion) from one plant is grafted onto the root stock of another plant. The stem will eventually grow into a new plant that is a combination of the two parent plants. 14 Layering is a method in which a part of the stem of a parent plant is bent down to the ground and covered with soil. The stem will eventually grow roots and form a new plant. 15 Air layering is a method in which a branch of a plant is induced to grow roots while still being attached to the parent plant. This is done by making a cut in the bark of the branch and then wrapping it with moist soil. The cut stimulates the growth of roots. Once the roots have developed, the branch can be separated from the parent plant and planted as a new plant. Extension / Follow-up Activities Growing Their Own Plants by Using Asexual Reproduction Methods 1 Divide students into groups to carry out a hands-on activity. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 55 © Praxis Publishing Singapore Pte. Ltd. 2 Ask students to choose a suitable plant and a method of asexual reproduction to grow the plant. This could be done by using roots, leaves, stems, stem cuttings or layering. 3 Let students observe the growth of their plants and learn about the different stages of plant development over time. 4 Record the growth of their plants on a sheet of paper. Ask students to take some photos during the different stages of plant development. 5 Ask each group to share the timeline of plant growth to the class. This helps in developing their communication skills. 6 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. Lesson 2.10 The Use of Reproductive Technologies Learning Outcomes • Understand the basic principles of different types of reproductive technologies • Apply the knowledge of reproductive technologies to make informed decisions about fertility treatment options Key Understanding Reproductive technologies are used in animals and plants to improve breeding, increase production and preserve endangered species. Some of the most common reproductive technologies used in animals include artificial insemination, embryo transfer and in vitro fertilisation (IVF). Some common reproductive technologies used in plants include artificial pollination and tissue culture. Although reproductive technologies have a number of benefits for both animals and plants, there are also some ethical concerns associated with the use of reproductive technologies. Induction 1 Begin by reviewing the basic concepts of animal reproduction. 2 Ask students what they know about reproductive technologies. Teaching and Learning Activities Textbook pp. 63–64 1 Explain what reproductive technologies are. 2 Introduce the different types of reproductive technologies in animals such as artificial insemination, embryo transfer and in vitro fertilisation (IVF). 3 Introduce the concept of artificial insemination (AI). Tell students that artificial insemination is used in a variety of animals. Ask students to give some examples of animals. Examples are cattle, sheep, goats, horses and dogs. 4 Describe the process of artificial insemination by using a figure to show its process flow. 5 Discuss the uses and benefits of artificial insemination in animal breeding. 6 Introduce the concept of embryo transfer. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 56 © Praxis Publishing Singapore Pte. Ltd. 7 Have students watch a video about embryo transfer by scanning the QR code below. 8 Describe the process of embryo transfer by using a figure to show its process flow. 9 Let students discuss the uses and benefits of embryo transfer. 10 Organise a field trip to a local farm or veterinary clinic where students can observe the process of artificial insemination or embryo transfer first-hand. (If time permits) 11 Introduce the concept of IVF. Ask students to watch a video about IVF in animals by scanning the QR code below. 12 Describe the different steps involved in IVF. 13 Discuss the benefits and risks of IVF. 14 Introduce animal cloning and how it works. 15 Let students to research the history and science behind animal cloning, including the ethical considerations and controversies about it. Textbook p. 65 16 Introduce the different types of reproductive technologies in plants such as artificial pollination and tissue culture. 17 Explain how artificial pollination works when compared with natural pollination. 18 Have students to simulate the process of artificial pollination using paintbrushes or cotton swabs to transfer pollen grains from one flower to another. 19 Let students discuss the advantages and disadvantages of artificial pollination. 20 Explain that plant tissue culture is a method that involves growing plants from small pieces of plant tissues in a nutrient medium. 21 Let students identify plants that use tissue culture for cultivation. 22 Explain the steps involved in plant tissue culture using a process flow diagram. 23 Ask students to carry out Activity 7 to find out more reproductive technologies that can help the reproduction of animals and plants. Share their findings with the class. 24 At the end of the lesson, ask students to answer some questions to test their understanding about reproductive technologies in animals and plants. • What are the different types of reproductive technologies used in animals? • How does artificial insemination work? • Are there any risks or side effects associated with IVF? • What are the different types of reproductive technologies used in plants? • What are the benefits of using reproductive technologies in plants? ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 57 © Praxis Publishing Singapore Pte. Ltd. Assessment and Evaluation 1 Assess students’ understanding of the use of reproductive technologies through their participation and responses in class discussions and activities. 2 Assess students’ digital skills and collaboration skills through Activity 7. 3 Assess students’ critical thinking skills through their answers to the questions at the end of the lesson. 4 Have students complete Exercises 1−3 Workbook p. 39 . 5 Provide feedback to students on their performance, highlighting areas where they have achieved and areas where they need to improve. Closure • To summarise the important ideas and concepts taught in the lesson, consider using the key points provided through strategies such as a class discussion, a summary statement, a quiz, a visual organiser or a reflective writing assignment. Allow students to ask any additional questions for clarification or to clear up any doubts. 1 Reproductive technologies are used in animals and plants to improve breeding, increase production and preserve endangered species. 2 Some common reproductive technologies used in animals include artificial insemination, embryo transfer and in vitro fertilisation (IVF). 3 Some common reproductive technologies used in plants include artificial pollination and tissue culture. Artificial Insemination (AI) and Embryo Transfer 4 Artificial insemination is a technique in which semen from a selected male is collected and introduced manually into the female reproductive tract to produce offspring with favourable characteristics. This technique is used in animal breeding. 5 Embryo transfer is a technique by which embryos are collected from a donor female and are transferred to one or more recipient females. It is used to propagate desirable genes from superior female animals. In Vitro Fertilisation (IVF) 6 In vitro fertilisation (IVF) is a technique in which eggs are fertilised with sperms outside the body in a laboratory. The resulting embryos are then transferred to the uterus in the hope of achieving a pregnancy. 7 IVF is used to obtain offspring of endangered animals, sterile animals or animals with low reproduction rates. Cloning 8 Animal cloning is a technique for the production of genetically identical copies of the desired animal. This is done by taking a cell from the donor animal and transferring its DNA to an egg cell that has had its own DNA removed. The egg cell develops into an embryo. The embryo is then implanted into the uterus of an adult female to grow. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 58 © Praxis Publishing Singapore Pte. Ltd. Artificial Pollination 9 Artificial pollination is a technique carried out by humans, and does not need the help of insects or wind. This technique involves manually transferring pollen grains with the desired characteristics from one flower to another. Tissue Culture 10 Tissue culture is a technique in which tissues taken from the parent plant are placed in a special growing medium containing nutrients and plant hormones. It is widely used to produce clones of a plant. • Ask students to reflect on what they have learned in this chapter by completing the sections ‘Recall’ Textbook p. 66 and ‘Concept Map’ Workbook p. 42 . • Let students complete ‘Objective Questions’ Workbook pp. 40–41 and ‘Online Quick Quiz’ Workbook p. 43 to check their mastery of this chapter. • To reinforce students’ critical thinking skills, have them answer the questions in ‘Put on your Thinking Cap’ Textbook p. 67 and ‘HOTS Daily Application’ Workbook p. 43 that require them to analyse, evaluate or create based on the knowledge they have acquired. • Give students a preview of what will be covered in the upcoming chapter to help them get ready. Extension / Follow-up Activities Selection of Suitable Reproductive Technologies for Animal Breeding 1 Divide students into groups to answer the following scenario. You are a dairy farmer with a herd of 100 cows. You want to increase your milk production by using reproductive technologies. What technologies would you consider? 2 Ask students to choose a suitable method of reproductive technology to breed the cows. 3 When choosing reproductive technologies, it is important to consider the following factors: • The species of animal • The desired traits of the offspring • The cost of the technology • The advantages of the technology • The success rate of the technology • The ethical implications of the technology 4 Ask students to collect information from what they have learned about different types of reproductive technologies. They also can get information from the Internet. 5 Allow students to consult with a veterinarian or animal reproduction specialist to get their recommendations. 6 Ask each group to prepare a presentation and share the selected method to the class. This helps in developing their communication skills. 7 When a group is presenting its outcomes, encourage other groups to think critically and to raise questions. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 59 © Praxis Publishing Singapore Pte. Ltd. Textbook Answers Recall p. 66 1 external; internal 2 binary fission 3 fragmentation 4 filament; pollen grains 5 stigma 6 pollination 7 wind 8 pollen tube; sperm cells 9 ovule; ovary 10 space 11 explosion 12 germination; oxygen 13 asexual; diploid; haploid 14 cones; young 15 asexual 16 vegetative; roots 17 grafting 18 reproductive Put on your Thinking Cap p. 67 1 Hydra reproduces by budding where a bud arises from the parent and develops into a new individual. Amoeba reproduces by binary fission in which the division of the nucleus is followed by the division of the cytoplasm, resulting in two individuals. 2 Insects help to disperse pollen grains. When an insect lands on a flower to suck its nectar, pollen grains will stick to its furry feet and body. 3 (a) Flowering plants reproduce sexually by producing flowers that contain the reproductive organs. During pollination, pollen grains from the male part of the flower are transferred to the female part, where they fertilise the eggs. The fertilised eggs develop into seeds within fruits. These seeds are dispersed and, under suitable conditions, germinate to form new plants. (b) The small seedlings grown in the garden may have come from the seeds dispersed through various external agents like animals, wind or water. Under favourable conditions, the seeds germinate into new plants. (c) The seeds of these fruits are usually dispersed through animal faeces when the animals consume them. Project: Creating a Hand Pollinator Textbook p. 68 1 Introduction (a) Introduce the concept of pollination. (b) Explain to students that they will design, create and test a hand pollinator to transfer pollen grains from one flower to another. ©Praxis Publishing_Focus On Science

Teacher’s Guide Focus-on Science Grade 9 60 © Praxis Publishing Singapore Pte. Ltd. (c) Give a brief overview of the steps involved in building a device to pollinate flowers. (Preparing materials needed, sketching designs of the device, building the device, testing the device, making improvements to the device, collecting the data, drawing a conclusion) (d) Set a deadline for them. 2 Material selection (a) Instruct students to choose and prepare materials they have at home to build the device. (b) Ask students to sketch a few designs and choose the best design to build the device. (c) Encourage students to identify one question they want to answer through the project. 3 Investigation planning and execution (a) Instruct students to plan their project, design and creation of the device. (b) Provide guidance and support as needed during the process of building the device. (c) Instruct students to carry out their project. (d) Encourage students to follow their planning carefully. (e) Instruct students to test their device and think about improvements to make. (f) Encourage students to collaborate with their peers and share ideas for enhancing their device’s functionality or design. (g) Remind students to record any changes they make and explain how it improved their device’s performance. 4 Reflection and presentation (a) Instruct students to reflect on what they have learnt in the process regarding the new knowledge and the improvements if they could repeat it. (b) Allow students to share their ideas and devices with the class. Encourage them to discuss the similarities and differences of their device designs with their friends. 5 Assessment Assess students based on their project plan, execution and presentation with the following criteria. (a) The accuracy, clarity and completeness of the project plan (b) The design and construction of the device (c) The ability to solve problems during the construction of the device (d) The accuracy and completeness of the data collected about the device’s performance and its design improvement (e) The ability to meet the deadline (f) The effectiveness of the report in communicating the ideas and design of the device (g) The creativity and innovation in the device design (h) The audience’s participation and engagement during the presentation ©Praxis Publishing_Focus On Science