... ... 3.1 Formative Practice Formative Practice 3.2 Brain Teaser Tease When resting, the pulse rate of an athlete is lower than the non-athletes. Why? 3.2.2 Aim: To gather the information on the human pulse rate. Instructions: 1. Carry out this activity in groups. Each group consists of four members. 2. Gather information about the human pulse rate in relation to: (a) health level (b) fitness level (c) emotions (d) stress 3. Obtain information from printed media, electronic media or interviews. 4. Pass your respective findings in a clockwise direction. The other members of the group must correct their friend’s findings if there is any error. 5. After 30 minutes, present your findings. Activity Simultaneous Round Table 21st Century Skills 1. What is the meaning of pulse rate? 2. Tick (✓) for the correct way of finding a pulse. 3. Ruzzana is pregnant. In your opinion, is Ruzanna’s pulse rate the same as a woman who is not pregnant? Justify your answer. 4. One day, Azril took his pulse. After running in a park near his home, Azril took his pulse again. In your opinion, will the pulse readings be the same? Justify your answer. 40
3.3.1 3.3.2 3.3 Blood Pressure Blood Pressure Measuring Instrument You learned about measuring blood pressure in Form 3. Blood pressure is the pressure applied by the blood on the walls of the blood vessels during blood circulation. Blood pressure is measured by using a sphygmomanometer. The unit for measuring blood pressure is millimetres of mercury and the symbol is mmHg. The best standard instrument to measure blood pressure is the sphygmomanometer that is used by medical practitioners in hospitals and clinics along with the stethoscope. Nevertheless, monitoring blood pressure at home can be done by using a digital sphygmomanometer. Measuring and Recording Blood Pressure Blood pressure is measured by taking two readings. The top number shows the pressure applied on the wall of blood vessels when the heart muscles contract. This pressure is systolic pressure. The bottom number shows the pressure applied on the wall of blood vessels when the heart muscle is resting (between heartbeats), and is called diastolic pressure. Both pressures are stated in millimetres of mercury (mmHg) because mercury was used in the first accurate pressure gauges and is still used as the standard unit of measurement for pressure in medicine. The measurement of blood pressure is recorded as systolic/diastolic (referred to as systolic per diastolic). Photograph 3.3 Digital sphygmomanometer Photograph 3.5 Measuring blood pressure Photograph 3.4 Sphygmomanometer Figure 3.7 Blood pressure reading 120/80 mmHg Systolic pressure Diastolic pressure 41 Techniques of Measuring the Parameters of Body Health Chapter 3
3.3.3 ... ... 3.2 Formative Practice Formative Practice 3.3 Blood Pressure Reading Regular blood pressure readings can help you to measure your body’s health levels. Blood pressure readings that are high and prolonged show that you might be experiencing high blood pressure. Blood pressure readings that are low and prolonged show that you might be experiencing low blood pressure. Table 3.1 shows blood pressure readings and their explanation. Table 3.1 Classification of blood pressure readings for adults Blood pressure category Systolic pressure (mmHg) Diastolic pressure (mmHg) Optimal Less than 120 Less than 80 Normal 120 – 129 80 – 84 At risk 130 – 139 85 – 89 High blood pressure stage 1 140 – 159 90 – 99 High blood pressure stage 2 160 – 179 100 – 109 High blood pressure stage 3 180 and above 110 and above (Source: Clinical Practice Guidelines on Management of Hypertension, 5th Edition, 2018) High blood pressure does not usually have any clear symptoms. If this problem is not well-controlled, it can lead to more serious problems such as stroke. The best way to track this problem is by having regular medical check-ups. Aim: To demonstrate the way to take a blood pressure reading. Instructions: 1. Carry out this activity in groups. 2. A student plays the role of a doctor while another student plays the role of a patient. 3. Prepare to play the character of a doctor taking the blood pressure reading of a patient. 4. Role play in front of the class. Activity Role-play 1. What is the meaning of blood pressure? 2. What is the instrument used to measure blood pressure? 3. State the steps of measuring blood pressure. 4. What are the effects of having high blood pressure? 5. Give four early prevention steps to avoid high blood pressure. 21st Century Skills 42
3.4 Body Mass Index (BMI) Calculating and Determining Body Mass Index Body Mass Index, commonly known as BMI, is the measurement of body mass against height. BMI can be calculated using a formula. ... ... 3.3 Spin-N-Think Science Science Gallery 3.4.1 Brain Teaser Tease BMI = Body mass (kg) (Height)2 (m2 ) Studies show that the lifespan of a person with an ideal BMI, which is, between 18.5 – 24.9 kg m-2 is longer than a person with a lower or higher BMI. Source: myHEALTH Portal What is the importance of knowing our BMI? BMI is a way to determine whether we have a body mass problem or not. After obtaining your BMI result, the chart in Table 3.2 below can be used to determine whether you are overweight, normal or underweight. Table 3.2 Body Mass Index chart BMI (kg m-2) < 18.5 18.5 – 24.9 25.0 – 29.9 30.0 or more Category: Underweight Desirable weight Overweight Obese What are factors that can cause a person to be overweight? Aim: To calculate and determine one’s BMI. Instructions: 1. Carry out this activity in groups. 2. The teacher supplies a spinning arrow. 3. Spin the arrow to determine which student needs to measure his/her BMI. 4. The student with the arrow pointed at him/her is the one who has to take his/her mass and height measurements. Calculate the student’s BMI together. 5. Repeat this activity until all the group members know their respective BMI. Activity Spin-N-Think 21st Century Skills 43 Techniques of Measuring the Parameters of Body Health Chapter 3
Formative Practice Formative Practice 3.4 Interpreting Body Mass Index Studies show that being overweight can cause serious health issues. Being overweight increases the risk of suffering from serious illnesses such as heart attack, high blood pressure, stroke, diabetes mellitus and complications of joints and bones. Being underweight can also increase the risk of acquiring health problems such as heart diseases, decrease in body's defence against diseases, fatigue, anaemia and depression. Nevertheless, achieving and maintaining an ideal body weight through a healthy diet and consistent physical activities can prevent these illnesses. Photograph 3.6 Malaysian Healthy Plate Ways to increase body mass • Practise healthy and balanced diet based on the Malaysian food pyramid and the Malaysian Healthy Plate • Eat at fixed times • Consume snacks that are packed with nutrients to increase calories • Eat more nutritious food Ways to decrease body mass • Set a realistic goal such as reducing half a kilogram of mass weekly • Monitor and record your body mass once a week • Eat healthy foods in moderation based on the Malaysian food pyramid and the Malaysian Healthy Plate • Make a few changes to your eating habits such as changing your food preparation method • Reduce or avoid food with high sugar or fat content • Do moderate exercises such as brisk walking, cycling and swimming for at least 30 minutes, three times a week • Gain support from those who are close to you Figure 3.8 Malaysian Healthy Plate Fish, Poultry, Meat and Legumes Fruits Vege at b el s Rice, Noodle, Bread, Cereals, Cereal Products and Tubers 1. What is the meaning of Body Mass Index? 2. What is the importance of calculating Body Mass Index? 3. If you have a BMI of 30.0, which category are you in? 4. What are the risks of being obese? 5. If we are underweight, will we be free of health issues? Justify your answer. 3.4.2 44
TECHNIQUES OF MEASURING THE PARAMETERS OF BODY HEALTH Body Temperature Definition Types of thermometers Techniques of measuring body temperature Body Mass Index (BMI) Definition Formula for calculating BMI Body Mass Index chart Pulse Rate Definition Pulse points on the body Factors affecting pulse rate Blood Pressure Definition Instrument for measuring blood pressure • High blood pressure • Low blood pressure Desirable weight Underweight Obese Overweight 45 Techniques of Measuring the Parameters of Body Health Chapter 3
Self-reflection Self-reflection Summative Practice Summative Practice 3 Objective Questions http://bukutekskssm. my/Science/F4/Q3 QUIZ After studying this chapter, you are able to: 3.1 Body Temperature Measure body temperature using the correct technique. Interpret body temperature readings. 3.2 Pulse Rate Identify the pulse points on the body. Carry out an experiment to determine the human pulse rate. 3.3 Blood Pressure Identify the instrument for measuring blood pressure. Measure and record blood pressure. Interpret data from blood pressure readings. 3.4 Body Mass Index (BMI) Calculate and determine Body Mass Index Interpret the Body Mass Index and make decisions on what to do next. 1. You have a fever if your body temperature is above 37ºC. Extreme cold can also cause body temperature to be below normal. (a) Based on the statement above, state three factors that can cause fever. (b) What is the normal body temperature? (c) Which type of thermometer is the most suitable for an infant who is less than 4 months old? 46
2. Photograph 1 shows two types of thermometers. P Q Photograph 1 (a) State the names of thermometer P and Q. (b) What are these thermometers for? (c) Suraya is 21 years old. Which thermometer is more suitable to measure her body temperature? (d) State the effects if a fever is allowed to continue without immediate treatment. 3. A student has carried out an experiment to investigate the pulse rate of four individuals of different ages. Table 1 below shows the readings that were obtained. Table 1 Age Pulse rate (bpm) 2 months 6 years 100 10 years 80 20 years 70 (a) Complete the table above. (b) State the: (i) manipulated variable (ii) responding variable (c) State the hypothesis from the experiment that was carried out. (d) What is the pulse rate of a trained athlete? 4. Fareeza attends a routine pulse check at the hospital. (a) Which part of the body is the pulse taken from by the nurse? (b) If Fareeza is a 22-year-old trained athlete, predict her pulse rate. (c) In addition to pulse check, Fareeza also goes for a blood pressure check. She finds that her blood pressure is normal. Predict her blood pressure reading. (d) How can Fareeza ensure that she is always healthy? 47 Techniques of Measuring the Parameters of Body Health Chapter 3
Mind Challenge Challenge 5. Siva checks his blood pressure for 3 continuous days. He finds that his blood pressure is approximately 150/95 mmHg each day. (a) What is the blood pressure reading of a normal person? (b) Based on the information above, state one inference on Siva’s condition. (c) What does Siva need to do next? 6. Generally, high blood pressure does not show any clear signs, but if it is not controlled, it will cause other health problems such as heart attack and stroke. (a) State other health problems that might be faced by a person with high blood pressure. (b) What instrument is used to measure blood pressure? (c) State the difference between systolic pressure and diastolic pressure. 7. Azni is 27 years old. She finds that her body temperature is not consistent. Can Azni use a rectal thermometer to measure her body temperature? 8. Excess body mass can increase the risk of acquiring serious illnesses. (a) State five serious illnesses that can be acquired if you have excessive body mass. (b) Nur Antasya is overweight. If you are a dietician who is treating her, what advice would you give to her. 9. The information below shows a list of foods that are sold during breakfast at the school canteen. Egg sandwich Fried noodles with fried egg Nasi lemak and spicy fried chicken Marissa is trying to lose weight. Which of these foods is suitable to be consumed by Marissa for breakfast? Justify your answer. 48
49 THEME Maintenance and 2 Continuity of Life • What do you know about Green Technology? • Is it safe for us to consume genetically modified foods? • Which system supports our body and protects our internal organs? • How are plants able to grow vertically against gravity? • What is hormone?
4 Green Technology for Environmental Sustainability Chapter Keywords Green Technology Socio-scientific issues Application of Green Technology 50
Digest Science Green Vehicle Era A green vehicle is an eco-friendly vehicle, that does not emit fumes into the environment. The examples of green vehicles are electric and solar cars. The electric car uses energy from the battery while the solar car uses solar energy from the Sun to move the motor in a vehicle. environmental sustainability energy sector waste and wastewater management sector agriculture and forestry sector transportation sector Green Technology and life What is the meaning of Green Technology? What are the available sectors within Green Technology? How do we apply Green Technology in our everyday life? You will learn about: 51 Green Technology for Environmental Sustainability Chapter 4
4.1 4.1.1 Environmental Sustainability Technological advancement and holistic development in this era have simplified and expedited various human tasks. However, the advancement of technology has also brought negative effects to the environment. For example, there is an increase in environmental pollution and a decrease of natural resources. Realising the extent of the current damage done to the environment, various initiatives have been introduced to spread the awareness on environmental sustainability. All the efforts and initiatives that have been carried out are regarded as Green Technology. Green Technology Concept Solar vehicles are used to reduce the use of fossil fuels Renewable energy sources are used to generate energy Photograph 4.1 Green Technology Concept Photograph 4.2 Examples of Green Technology in daily life Important in: • overcoming the destruction of the environment • reducing carbon emissions • improving human health and lifestyle • conserving the country’s natural resources by applying renewable energy sources Green Technology is the development and application of products, equipment and systems used to conserve the environment and nature, as well as minimising and reducing the negative effects of human activities. 52
If we look at the four pillars above, they clearly show that Green Technology emphasises on the aspect of energy efficiency. Do you still remember the topic on energy efficiency that you studied in Form 3? Energy efficiency refers to the use of less energy to carry out work at the same or higher rate without affecting the production and the quality of the desired outcome. My Nation Lebih Banyak Bintang Lebih Jimat Tenaga More Stars More Energy Saving Penggunaan Tenaga Purata Setahun Produk Ini Menggunakan % Kurang Tenaga Daripada Produk Biasa This Product Consumes % Less Energy Than An Average Product Diuji Mengikut / Tested According to xxx XXX kwj kwh www.st.gov.my Energy Commission Average Energy Consumption Per Year Jenis peralatan Jenama dan Model PENGGUNAAN TENAGA 5 ENERGY CONSUMPTION 5 4.1.2 Figure 4.1 Energy efficiency label When energy efficiency is given priority in a country through the practice of Green Technology, then: (a) energy conservation can be increased (b) the country’s economy can be strenghtened and wastage can be reduced (c) wastes can be converted into a cleaner and safer form of renewable energy Malaysia strongly supports and is committed to sustainable energy efficiency. Among the initiatives and efforts carried out in the implementation of energy efficiency are: • the implementation of energy efficiency labels for electrical appliances (Figure 4.1) • Green Building Index (GBI) • energy efficiency technology campaigns • using electricity from solar source campaigns • consumer awareness campaigns through energy-saving practices There are four main pillars that uphold the National Green Technology Policy: • energy – promoting energy efficiency and seeking energy independence • environment – minimising negative effects and conserving the environment • economy – enhancing the country’s economy through the use of technology • social – improving the quality of life for all Green Building Index (GBI) is a rating system given to buildings with environmentally-friendly features. Raja Haji Fi Sabilillah mosque in Cyberjaya is the first mosque in Malaysia to receive this recognition. First ‘Green’ Mosque in Malaysia http://bukutekskssm.my/ Science/F4/Pg53 Relating Energy Efficiency to Green Technology For Green Technology to succeed in our country, the National Green Technology Policy was launched in July 2009. What are the pillars of that policy? Let us look at the following note: INFORMATION 53 Green Technology for Environmental Sustainability Chapter 4
4.1.3 Sectors in Green Technology Green Technology is divided into several sectors for a more focused implementation. Let us identify each sector that is involved in this Green Technology. Agriculture and Forestry Sector – Focuses on controlling the rate of carbon dioxide in the air through agriculture and forestry. This sector also emphasises soil nutrient care and improvement in agriculture practices. Energy Sector – Focuses on the use of a cleaner and carbon-free alternative energy that can replace the use of fossil fuels. Among the examples of alternative energy is renewable energy such as hydroelectric, solar and wind. Transportation Sector – Focuses on the improvement of a cleaner transportation infrastructure, vehicle fuel and public transportation. Waste and Wastewater Management Sector – Focuses on minimising waste disposal and wastewater into the environment by converting waste or wastewater into something new such as compost. 54
4.1.3 Formative Practice Formative Practice 4.1 Industrial and Manufacturing Sector – Focuses on energy efficiency and energy management programmes to reduce the negative effects of the greenhouse effect, haze and acid rain. 1. What is the meaning of Green Technology? 2. State two importance of energy efficiency. 3. State the sectors that can be found in Green Technology. Building Sector – Focuses on Green Building construction, for example the Diamond Building, which is the Energy Commission headquarters that emphasises close scrutiny of the environment and the building, use of green construction materials, efficient use of energy and water, and good solid waste management. Information and Communications Technology (ICT) Sector – Focuses on the practice of green ICT in the manufacturing, design, use and disposal of computer equipment. Green ICT aims to reduce the use of dangerous materials by using biodegradable materials and also to conserve energy. Photograph 4.3 Sectors in Green Technology The Diamond Building http://bukutekskssm. my/Science/F4/Pg55 INFORMATION 55 Green Technology for Environmental Sustainability Chapter 4
4.2.1 4.2 Energy Sector Socio-scientific Issues An increase in the population growth rate raises our daily needs in all aspects. This has a direct impact on the environment and natural resources, thus causing various socio-scientific issues. Socio-scientific issues are open problems that are controversial social issues related to science. These issues also emphasise moral and scientific applications on real-world situations. Figure 4.2 shows several socio-scientific issues that are related to the environment. Socio-scientific issues arise as a result of human activities. Emissions of greenhouse gases resulting from human activities cause climate change phenomena. The greenhouse effect causes draughts, flash floods, an increase in Earth’s temperature, thunderstorms and the destruction of biodiversity. Global warming Deforestation Air pollution Water pollution Indiscriminate waste disposal Figure 4.2 Socio-scientific issues related to the environment 56
... ... 4.1 4.2.2 Socio-scientific Issues in the Energy Sector Let us take a closer look at the socio-scientific issues in the energy sector. Photograph 4.4 Socio-scientific issues in the energy sector Aim: To understand the socio-scientific issues in the energy sector. Instructions: 1. Carry out this activity in groups. 2. Carry out active reading and discuss: (a) socio-scientific issues in the energy sector (b) factors that contribute to the socio-scientific issues in the energy sector (c) application of Green Technology in overcoming socio-scientific issues in the energy sector 3. Present the outcome of your group discussion using a multimedia presentation. Activity Result Showcase 21st Century Skills The burning of fossil fuels produces greenhouse gases such as carbon dioxide in large amounts and this causes global warming to become increasingly critical. The burning of fossil fuels causes extreme climate changes that lead to long draughts and various natural disasters. The use of non-renewable energy sources such as petroleum, coal and natural gas increases each year according to the needs of the countries around the world. If this continues, it would not be long before fossil fuels are depleted. 57 Green Technology for Environmental Sustainability Chapter 4
4.2.3 Kenyir Dam in Terengganu is the largest hydroelectric dam in Peninsular Malaysia. This dam controls the overflowing flood water and generates electricity for our country. My Nation Application of Green Technology to Overcome Socio-scientific Issues in the Energy Sector The energy sector is the main sector in Green Technology. Two aspects that are emphasised in Green Technology for solving socio-scientific issues related to the energy sector are: (a) how energy is produced or supplied (b) efficiency in usage and distribution of energy produced Let us look at Figure 4.3, which shows several examples of renewable energy that can be developed to replace fossil fuels. Wind energy source is a clean energy source that can replace fossil fuel in the future. Figure 4.3 Application of Green Technology in the energy sector Hydro energy source is a renewable energy source that has become one of the main energy sources in the world to generate electricity. 58
Hot water Cool water 4.2.3 By maximising the usage of renewable energy in Green Technology, we are able to reduce the content of carbon dioxide in the air. This indirectly reduces the greenhouse effect and climate change that contribute to the problems discussed on page 57. Besides promoting renewable energy, a holistic energy efficiency practice has been proposed in the implementation of Green Technology. This has managed to create awareness among electrical equipment manufacturers to produce efficient appliances. It is also proposed that consumers should save electricity such as switching off electrical appliances when they are not in use, adjusting the air-conditioner temperature at home and the office to 24°C – 25°C, besides using energy efficient electrical appliances. Solar energy source is a renewable energy source that has potential to be developed as Malaysia gets enough sunlight throughout the year. Geothermal energy source is also a suitable alternative energy to replace fossil fuel. However, it needs suitable geographical factors. 59 Green Technology for Environmental Sustainability Chapter 4
4.3.1 4.3 Formative Practice Formative Practice 4.2 Waste and Wastewater Management Sector Sewage, chemical wastes and rubbish that are disposed into the rivers and seas interfere with the ecosystem of rivers, seas and the surrounding areas. Food leftovers that are not properly disposed of cause environmental pollution. Around 268 million tons of paper is produced in a year. To produce 1 ton of paper only, we need 2 to 4 tons of timber. Paper is also a contributor of solid waste. Production, management and decomposition of solid waste contribute to an increase in greenhouse gases. This causes climate change around the world. Socio-scientific Issues in the Waste and Wastewater Management Sector In this modern era, the public should be made more aware of solid waste and wastewater management. This is because a change in lifestyle and socio-culture, rapid development in infrastructure and economy plus the growing number of global inhabitants have increased solid waste and wastewater disposal. Let us look at these issues in more detail. Photograph 4.5 Socio-scientific issues in the waste and wastewater management sector 1. State three socio-scientific issues related to the energy sector. 2. What measures should be taken to conserve energy? 60
4.3.2 ... ... 4.2 Formative Practice Formative Practice 4.3 Application of Green Technology to Overcome Socio-scientific Issues in the Waste and Wastewater Management Sector The application of Green Technology has managed to prepare an effective platform for waste and wastewater management. It has succeeded in reducing the greenhouse effect efficiently besides saving costs. Let us look at the applications of Green Technology in waste and wastewater management. 1. State two socio-scientific issues in the waste and wastewater management sector. 2. State two methods to overcome the problems in the waste and wastewater management sector. Aim: To understand socio-scientific issues in waste and wastewater management sector. Instructions: 1. Carry out this activity in groups. 2. Gather information and discuss: (a) socio-scientific issues in the waste and wastewater management sector (b) factors that contribute to the socio-scientific issues in the waste and wastewater management sector (c) application of Green Technology in overcoming socio-scientific issues in the waste and wastewater management sector 3. Present the outcome of your group discussion using a multimedia presentation. Activity Result Showcase Prevention and reduction • Consumers are encouraged to control paper usage by recycling paper or using paper only when it is necessary. • Consumers are advised to prepare sufficient food for the whole family in order to prevent food wastage. Sorting and recycling • Since 2015, the government has been encouraging all households to sort their household waste. By doing this, we are able to reduce the disposal of recyclable materials while at the same time solid waste at landfills are lessened. Refuse, Reduce, Reuse, Recycle and Recovery (5R) • The 5R concept, which is Refuse, Reduce, Reuse, Recycle and Recovery, has been introduced to replace the previous 3R concept. The addition of the two ‘R’s at the beginning and at the end – ‘refuse’ and ‘recovery’ – is aimed at achieving zero waste. How do you practise the 5R concept at home? Treatment and processing (biological process) • Biological treatment process of solid waste enables waste to be converted into beneficial organic substances such as organic fertilisers. • This process also converts solid waste into a main source of renewable energy (biomass) that is capable of replacing fossil fuel. 21st Century Skills 61 Green Technology for Environmental Sustainability Chapter 4
4.4 4.4.1 Agriculture and Forestry Sector Socio-scientific Issues in the Agriculture and Forestry Sector An increase in population density and change in lifestyle are among the factors that contribute to the high demand for new settlement areas, sufficient food supply and good transportation route. At a glance, these issues are not big problems. In fact, they make our lives easier. Did you know that these issues would become a huge disaster if they are not controlled and regulated properly? Photograph 4.6 Socio-scientific issues in the agriculture and forestry sector Deforestation for the purpose of development is meant for a new settlement area or agriculture. If this is not controlled and regulated properly, this would lead to landslides, floods and the extinction of flora and fauna. Open burning carried out by farmers on their farms can cause severe haze. If this continues, it would compromise the air quality throughout the country and neighbouring countries. Massive forest exploration would interfere with the gas cycle of Earth. This is because forests are like the ‘lungs of Earth’. The conversion of carbon dioxide into oxygen can only be done by plants during photosynthesis. 62
4.4.1 Landslide on the Kuala Lumpur-Karak Highway on 11 November 2015 was believed to be caused by indiscriminate logging in Lentang Forest Reserve. Chemical substances absorbed by the soil would also flow into the nearby rivers. This would contaminate the rivers. Widespread use of pesticides and chemical fertilisers cause soil pollution of agriculture land. For example, the acidity of the soil increases thus making it not suitable for agriculture. High demand for furniture and indiscriminate paper usage cause massive deforestation because furniture and paper originate from trees. 63 Green Technology for Environmental Sustainability Chapter 4
... ... 4.3 Science Career 4.4.2 Application of Green Technology to Overcome Socio-scientific Issues in the Agriculture and Forestry Sector We have seen several socio-scientific issues in the agriculture and forestry sector. Therefore, several measures have been introduced through Green Technology to restore the existing forests, and at the same time protect the agricultural yield. Replanting trees can maintain the existing species. Aim: To understand the socio-scientific issues in the agriculture and forestry sector. Instructions: 1. Carry out this activity in groups. 2. Gather information and discuss: (a) socio-scientific issues in the agriculture and forestry sector (b) factors that contribute to the socio-scientific issues in the agriculture and forestry sector (c) application of Green Technology in overcoming socio-scientific issues in the agriculture and forestry sector 3. Present the outcome of your group discussion using a multimedia presentation. Result Showcase Photograph 4.7 Application of Green Technology in the agriculture and forestry sector Forest Ranger A forest ranger has to guard and coordinate forest development projects, factory-operation enforcement and trespassing of recreational forests. A forest ranger must also check and monitor forest operation licencing for timber-based industries, enforce the forestry law and take actions when necessary. Treating and processing agricultural waste into compost is a Green Technology practice that is capable of controlling the balance of nature. Logging activities have to be regulated in order to conserve forest resources. Besides that, more forest reserves have to be gazetted to maintain a balanced ecosystem in the forest. Activity 21st Century Skills 64
Formative Practice Formative Practice 4.4 4.5 4.5.1 1. What causes landslides and mud floods to happen? 2. State the effect of using excessive chemical fertilisers in agriculture. 3. State two measures that can be taken to reduce deforestation. Transportation Sector The transportation sector is among the main sectors in Green Technology. This sector is one of the main contributors to air pollution. Let us look closely at the issues in this sector. History Corner In July 1954, there was a major air pollution in Los Angeles. The city was covered in photochemical smog when nitrogen oxide and hydrocarbon from vehicle fumes reacted with the surrounding air and ultraviolet rays from the Sun. Fumes emitted by vehicles contain gases such as carbon dioxide and carbon monoxide. Both are greenhouse gases. The presence of these gases causes the greenhouse effect that contributes to drastic climate change. 95% of motorised vehicles used today run on petrol and diesel. Petrol and diesel are obtained from petroleum. About 60% of the petroleum in the world is used in the transportation sector. Therefore, petroleum which is a non-renewable source of energy, can deplete. 65 Green Technology for Environmental Sustainability Chapter 4
... ... 4.4 4.5.1 4.5.2 Dangerous gases emitted from vehicles can cause acid rain. Acid rain destroys plants, corrodes buildings and irons, and damages tyres on vehicles. Issues in the transportation sector need holistic awareness from everyone. Through Green Technology, efforts in preventing air pollution whilst ensuring sustainability of life can be implemented well. Let us look at the measures and efforts taken in Green Technology. Application of Green Technology to Overcome Socio-scientific Issues in the Transportation Sector Green Transportation Pedestrian Bicycle Public transportation Service vehicle Taxi Multiple occupant vehicle Single occupant vehicle Mode of green transportation Green transportation refers to any form of transportation that releases very minimal greenhouse gases or none at all. For example, vehicles that use renewable energy. Among the forms of green transportation are walking, cycling and using green vehicles. Aim: To understand socio-scientific issues in the transportation sector. Instructions: 1. Carry out this activity in groups. 2. Gather information and discuss: (a) socio-scientific issues in the transportation sector (b) factors that contribute to the socio-scientific issues in the transportation sector (c) application of Green Technology in overcoming socio-scientific issues in the transportation sector 3. Present the outcome of your group discussion using a multimedia presentation. Activity Result Showcase Photograph 4.8 Socio-scientific issues in the transportation sector 21st Century Skills 66
4.5.2 Science Science Gallery The Melaka State Government is very committed to the application of Green Technology in the state. Melaka has begun using electric buses to transport passengers around the city. Visit the website below or scan the QR code to know more about the electric buses in Melaka. INFORMATION Electric Buses in Melaka http://bukutekskssm.my/ Science/F4/Pg67 Invention of Natural Gas Vehicle (NGV) Natural gas vehicles use either liquefied natural gas (LNG) or compressed natural gas (CNG). Today, vehicles that rely on petrol can be modified to use LNG or CNG. Biofuel as an alternative for petroleum Malaysia has begun using biofuel. Biofuel is an alternative source that refers to fatty acid methyl ester that is produced from plant oils and animal fats. It is obvious that this is a renewable energy source and it is more environmentally-friendly. Photograph 4.9 Application of Green Technology in the transportation sector 67 Green Technology for Environmental Sustainability Chapter 4
Formative Practice Formative Practice 4.5 4.6 4.6.1 Transport Electricity Emissions Water Fuel Gas Recycling Waste Carbon offset CO2 INFORMATION 1. State the consequences if the number of vehicles using fossil fuel increases. 2. Biofuel is that is produced from and . Green Technology and Life Global warming and drastic climate change issues are the hot topics of discussion throughout the world. Severe consequences of global warming await us if the global community fails to realise the effects of rapid development without considering our surroundings. Therefore, what should we do to address this issue? We tend not to realise that activities we carry out every day increase carbon footprint. Carbon footprint is the amount of greenhouse gas, such as carbon dioxide, released into the atmosphere as a result of human activities such as open burning and burning of fossil fuels (Figure 4.4). Therefore, we should apply Green Technology in our life so that we can reduce the amount of carbon dioxide that is being released into the environment and hence, reduce carbon footprints at the same time. Photograph 4.10 Students participating in an exhibition of green city design innovation in conjunction with the International Greentech and Eco Products Exhibition and Conference (IGEM) in Kuala Lumpur Low Carbon Footprint could Reduce the Impact of Climate Change http://bukutekskssm.my/ Science/F4/Pg68 Figure 4.4 Carbon footprint Role of Individuals in Managing Global Warming and Climate Change in order to Reduce Carbon Footprint 68
Formative Practice Formative Practice 4.6 1. The figures below show the activities carried out by Mariam and her father. What are the advantages of the activities carried out by them? Explain your answer by using the Green Technology concept. 2. In your opinion, what is the effect on the environment when we implement Green Technology? 4.5 4.6.1 Aim: To implement awareness campaigns through the Internet on issues pertaining to global warming and climate change phenomena. Instructions: 1. Carry out this activity in groups to study the following statement. The phenomena of global warming and climate change is plaguing our world now and need to be given serious attention. The phenomena have resulted in many extreme effects on Earth. It is therefore important that we reduce these problems by applying our knowledge on Green Technology to ensure environmental sustainability for the future generations. 2. Discuss and gather relevant information from academic journals or websites. 3. Create an online awareness campaign to overcome global warming and climate change phenomena for the sustainability of living things on Earth. Activity STEM Project 69 Green Technology for Environmental Sustainability Chapter 4
GREEN TECHNOLOGY FOR ENVIRONMENTAL SUSTAINABILITY Socio-scientific issues • Indiscriminate waste disposal • Release of greenhouse gases • 5R practice • Biological treatment and waste processing Socio-scientific issues • Uncontrolled forest exploration • Use of pesticides and chemical fertilisers Socio-scientific issues • Increase in the number of vehicles • Production of vehicle fumes that contain dangerous gases • Recycling • Usage of compost • Replanting • Practice of green vehicle mode • Use of biofuel • Renewable energy sources • Energy efficiency Industrial and Manufacturing Sector Building Sector Information and Communications Technology Sector Energy Sector Socio-scientific issues • Use of non-renewable energy sources • Burning of fossil fuels Waste and Wastewater Management Sector Transportation Sector Agriculture and Forestry Sector Sectors in Green Technology Application of Green Technology Application of Green Technology Application of Green Technology Application of Green Technology Socio-scientific issues Definition of Green Technology 70
Self-reflection Self-reflection Summative Practice Summative Practice 4 Objective Questions http://bukutekskssm. my/Science/F4/Q4 QUIZ After studying this chapter, you are able to: 4.1 Environmental Sustainability Define and justify Green Technology in life. Relate the energy efficiency to Green Technology. Identify sectors in Green Technology. 4.2 Energy Sector Describe socio-scientific issues. Explain socio-scientific issues in the energy sector. Justify the application of Green Technology to overcome socio-scientific issues in the energy sector. 4.3 Waste and Wastewater Management Sector Explain socio-scientific issues in the waste and wastewater management sector. Justify the application of Green Technology to overcome socio-scientific issues in the waste and wastewater management sector. 4.4 Agriculture and Forestry Sector Explain socio-scientific issues in the agriculture and forestry sector. Justify the application of Green Technology to overcome socio-scientific issues in the agriculture and forestry sector. 4.5 Transportation Sector Explain socio-scientific issues in the transportation sector. Justify the application of Green Technology to overcome socio-scientific issues in the transportation sector. 4.6 Green Technology and Life Justify the role of individuals in addressing the phenomena of global warming and climate change in reducing carbon footprint. 1. Read the extract below. Green Technology practices proposed in the National Green Technology Policy have been infused in lessons at schools. The awareness of environmental sustainability through Green Technology should be inculcated from a young age. Based on the extract above: (a) what is meant by Green Technology? (b) state the four pillars of the National Green Technology Policy. 71 Green Technology for Environmental Sustainability Chapter 4
2. The statement below explains energy efficiency. Energy efficiency is using less energy to carry out work at the same or higher rate without affecting the production and the quality of the desired outcome. Based on the statement above: (a) state the importance of energy efficiency in everyday life. (b) give an energy efficiency practice that you can carry out at home. Explain your answer. 3. The following statement is pinned on the school noticeboard. In order to enable a holistic implementation of Green Technology practices, several sectors have been created for a more direct and focused implementation. (a) State three sectors found in Green Technology. (b) Explain each sector mentioned in question 3(a). 4. Photograph 1 shows a socio-scientific issue in the energy sector. Photograph 1 (a) State the effects of the issue on the environment. (b) Suggest two methods to overcome the issue through Green Technology. (c) State one advantage of using Green Technology in overcoming the issue. (d) Do you agree that the use of Green Technology in our life reduces environmental pollution? Justify your answer. 72
5. Read the statement below. • Fumes from vehicles that use fossil fuel are among the main contributors to the increase of carbon dioxide in the air. • Acid rain destroys forests and corrodes metal and concrete. (a) Explain the transportation sector in Green Technology practices. (b) Explain two appropriate measures that can be taken in the transportation sector to overcome the issues mentioned in the statement. Mind Challenge Challenge 6. Azman likes farming. He decides to plant mustard in one corner of his house. However, he does not have a suitable container for planting. Help Azman to plan how to recycle materials at his home to solve his problem. You can use labelled sketches to support your answer. Materials: Sketch: 73 Green Technology for Environmental Sustainability Chapter 4
DNA Nucleotides Chromosomes Karyotype Mitosis Meiosis Dominant allele Recessive allele Mendel’s Law Genotype Phenotype Mutation Keywords 5 Genetics Chapter 74
DNA Evidence You might have watched popular crime investigation dramas on the television. The dramas are very interesting as they give us exposure to investigation techniques in forensic science. Crime cases can be solved by collecting DNA evidences. DNAs left behind by the criminal can be identified by an investigator or forensic scientist using modern techniques and equipment. In a criminal case, the criminal might leave evidences such as fragments of skin, hair or droplets of blood at the crime scene. Forensic scientists can analyse the DNA from these specimens by comparing these DNA samples to the suspect’s DNA. Digest Science cell division inheritance mutation genetic engineering technology variation What is meant by cell division process? Is it true that our characteristics can be inherited? What is mutation? How does genetic engineering affect our daily life? You will learn about: Genetics Chapter 5 75
5.1 Cell Division 5.1.1 Figure 5.1 Chromosome, gene and DNA Gene, Deoxyribonucleic Acid (DNA) and Chromosomes You learned about cells and cell division in Form 1. You have also learned that nucleus is a structure in the cell which controls all activities in the cell. Do you know which substance in the nucleus controls the cell division process? Chromosomes are fine thread-like structures which consist nucleic acids and protein. They are long and spiral structures located in the nucleus. Each chromosome contains a long DNA molecule. Nucleus contains chromosomes. Chromosomes Nucleus Cell 76
3D Model 5.1.1 Deoxyribonucleic acid or DNA is made up of basic units known as nucleotides. Each unit of nucleotide consists of three components, deoxyribose sugar, a nitrogenous base and a phosphate group. DNA is made of two twisted antiparallel polynucleotide chains forming a structure known as double helix. DNA A gene is a basic hereditary unit that determines an individual’s characteristics. The function of the gene is to control the inherited characteristics in an organism such as tongue-rolling ability in humans, the shape of the green pea and the colour of the cat’s fur. Genes are arranged as segments in the DNA along the chromosomes. There are thousands of genes in a DNA molecule. Gene Science Science Gallery Genetics is a study of genes, hereditary and variations in organisms. Genetics Chapter 5 77
5.1.1 Science Science Gallery Each chromosome has several types of genes, from 200 – 300 genes for each chromosome. Chromosome structure: C.H YEN A gene that programs the colour of the skin A gene that programs the colour of the hair 1 2 3 4 5 6 7 8 9 10 11 12 13 19 20 21 22 X Y 14 15 16 17 18 Kariotip lelaki 1 2 3 4 5 6 13 14 15 16 19 20 21 22 17 18 7 8 9 10 11 12 XX Kariotip perempuan Centromere One chromatid Sister chromatids We can simplify the relationship between the three as in Figure 5.2 below. Figure 5.2 Relationship between chromosome, DNA and gene Each species on Earth has a fixed number of chromosomes. The human body cell contains 46 chromosomes. Each chromosome exists in pairs of similar shapes and sizes. Such a pair of chromosomes is known as homologous chromosomes. The human homologous chromosomes can be arranged according to their shapes and sizes. Figure 5.3 shows the arrangement of human homologous chromosomes. This arrangement is called karyotype. Figure 5.3 Human karyotype In humans, the chromosomes can be divided into two, autosomes and sex chromosomes. Autosomes carry genes that control characteristics such as the colour of the eyes, ability to roll the tongue and the type of hair of a human. Sex chromosomes on the other hand, carry genes that determine gender, whether male or female. Chromosome DNA Gene Male karyotype Female karyotype Chromosome http:// bukutekskssm.my/ Science/F4/Pg78 INFORMATION 78
5.1.2 Science Science Gallery The human somatic cell has 46 chromosomes but the human gamete cells, sperm and ovum, have only half the number of chromosomes, 23 chromosomes. Science Science Gallery Cancer is caused by uncontrolled and abnormal cell division. These cells divide faster than they are supposed to in normal conditions. Cancer cells Mitosis and Meiosis How are genes inherited? To know further, we have to understand cell division first. There are two types of cell division that take place in a cell, mitosis and meiosis. Mitosis is a cell division process that forms two identical daughter cells, each having the same number of chromosomes and genetic content as the parent cell. Mitosis takes place in the somatic cells of the human and animal bodies. Mitosis also takes place in the meristematic tissue such as the tip of the roots and the shoot of the plants. Figure 5.5 shows the stages in mitosis. Meiosis is a process where the cell divides into four distinct cells, each containing half the number of chromosomes in the parent cell. Meiosis takes place in the reproductive organ to produce gametes for sexual reproduction. Meiosis in humans takes place in the male’s testes and the female’s ovary. In plants, meiosis takes place in the anther and the ovary. Figure 5.6 shows the stages in meiosis. Figure 5.4 Human chromosomes Chromosomes Sex chromosomes Sex chromosome X Sex chromosome Y Autosomes Science Science Gallery Interphase is the stage before the process of mitosis and meiosis occurs. At this stage, DNA replication occurs and cells undergo growth and prepare for cell division. Nuclear Chromosome membrane Genetics Chapter 5 79
5.1.2 Figure 5.6 Meiosis Figure 5.5 Mitosis Meiosis http://bukutekskssm.my/ Science/F4/Meiosis_Pg80.mp4 Mitosis Meiosis VIDEO Chromosome Centromere Spindle fibre Meiosis I Nuclear Nucleolus membrane Prophase Metaphase Chromosomes are arranged in an equatorial plane. The spindle fibres are attached to the centromere. Centromere splits into two, each sister chromatid separates and moves towards the opposite poles of the cell (polarisation). Chromosomes shorten and thicken and later become visible. Each chromosome consists of two chromatids joined at the centromere. Spindle fibres begin to form. Nuclear membrane and nucleolus disintegrate. Anaphase Prophase I Metaphase I Anaphase I Telophase I Chromosomes are arranged in an equatorial plane. The spindle fibres are attached to the centromere. Chromosomes shorten and thicken and then become visible. Homologous chromosomes pair together. Crossing over occurs, that is the exchange of genetic information between the homologous chromosomes. Cytoplasm divides. Last stage of meiosis I ends. Homologous chromosomes separate and move towards the opposite poles of the cell. 80
5.1.2 Mitosis http://bukutekskssm.my/ Science/F4/Mitosis_Pg81.mp4 VIDEO Meiosis II Nuclear membrane Nucleolus Chromatids reach the opposite poles. Nuclear membrane and nucleolus are formed again. Two daughter cells with the same number of chromosomes and genetic information as the parent cell are formed (diploid). Telophase Cytoplasm divides. Prophase II Metaphase II Spindle fibres begin to form. Four non-identical daughter cells (gametes) with half the number of chromosomes of the parent cell (haploids) are formed. Centromere splits into two. The sister chromatids separate and move towards the opposite poles of the cell (polarisation). Chromosomes are arranged in an equatorial plane. The spindle fibres are attached to the centromere. Anaphase II Telophase II Genetics Chapter 5 81
Produces two daughter cells Crossing over does not occur No variation Daughter cell are genetically identical to their parent cells The number of chromosomes of the daughter cell is the same as that of the parent cell Takes place in the somatic cell Produces four daughter cells Crossing over occurs Has variations Daughter cells are genetically not identical to their parent cells Takes place in the reproductive cell The number of chromosomes of the daughter cell is half of the parent cell Cell division DNA replication Mitosis Meiosis Figure 5.7 Similarities and differences between mitosis and meiosis The Importance of Mitosis and Meiosis 5.1.2 5.1.3 Figure 5.7 shows the similarities and differences between mitosis and meiosis. Can anyone share the importance of mitosis and meiosis? I know, teacher. Mitosis is important for the growth of organisms and meiosis is important for the production of gametes. Good, Raymond! You gave the correct answer. Mitosis is important to replace damaged or dead cells when we are injured. Mitosis is also important in asexual reproduction for organisms such as Amoeba sp.. Mitosis produces new cells which are identical to the parent cells. If my skin is injured, the healthy cells will carry out mitosis to produce new cells. As a result, my wound will be healed. 82
5.1.3 Formative Practice Formative Practice 5.1 5.1 Photograph 5.1 Growth process that takes place at the tip of the root of a plant Figure 5.9 Asexual reproduction in Amoeba sp. Figure 5.8 Process that replaces damaged cells 1. What is meant by (a) gene (b) chromosomes (c) DNA 2. Where do mitosis and meiosis take place in the human body? 3. State the similarities and differences between mitosis and meiosis. Wound Mitosis Activity Aim: To create a multimedia presentation on the importance of mitosis and meiosis. Instructions: 1. Carry out this activity in groups. 2. Gather information: (a) the importance of mitosis in the growth process, replacement of damaged cells and asexual reproduction (b) the importance of meiosis in the production of gametes 3. Use various sources such as the Internet and the library to gather the information above. 4. Present the outcomes of your group discussion in the form of multimedia presentation. Multimedia Presentation 21st Century Skills Genetics Chapter 5 83
Science Science Gallery What is the difference between characteristics and traits? Characteristics are tangible properties that are inherited and determined by genes such as the colour of the pupil. Traits are variants for specific characteristics that differentiate individuals. So, the traits for the colours of the pupils are black, brown and blue. 5.2 Inheritance Inheritance in Humans Look at the following family photographs. Do they look identical? Do children inherit all the characteristics of their parents? Each child inherits certain characteristics from their parents. The transmission of these characteristics from the parents to the children is known as inheritance. 5.2.1 Photograph 5.2 Inheritance of characteristics in humans Characteristics such as the types of hair and the colours of pupils are examples of characteristics that can be inherited by the children from their parents. These characteristics are passed down from the parents to the children through genes. As you have studied in subtopic 5.1, genes are the basic units of inheritance found in the chromosomes. Genes control certain characteristics in an organism. A pair of genes at the same locus or position in the homologous chromosome will control one trait of the organism. The pair of genes at the same locus is known as the allele. Alleles can be found in dominant or recessive forms. 84
Brain Teaser Tease Is dimple a dominant or recessive trait? 5.2.1 The characteristics that are controlled by the dominant allele will be shown whereas the recessive allele will be covered. The recessive allele would only show the characteristics it controls when dominant allele is absent. Therefore, the recessive characteristics would only be shown when both alleles are recessive. The dominant allele is represented by capital letters while the recessive allele is represented by small letters. For example, ‘T’ is used to represent tall and ‘t’ represents short. Colour of eyes Type of blood Colour of hair D Type of hair d C c B b A a Figure 5.10 Example of dominant and recessive alleles in chromosomes Figure 5.10 shows a pair of homologous chromosomes in the nucleus. For every trait, we inherit two copies of the genes, one from our mother and the other from our father. Capital letters A, B, C and D represent the dominant alleles while the small letters a, b, c and d represent the recessive alleles. Do you know which human traits are dominant and recessive? Table 5.1 shows some dominant and recessive traits in humans. Table 5.1 Examples of dominant and recessive traits in humans Dominant trait Recessive trait Ability to roll the tongue Inability to roll the tongue Black hair Blonde hair Free earlobes Attached earlobes Attached earlobe Free earlobe Photograph 5.3 Attached earlobe and free earlobe Genetics Chapter 5 85
Inheritance Mechanism Gregor Mendel is the first person to discover the inheritance mechanism in a systematic and detailed manner. Mendel used pure-breeding pea plant in his experiment on monohybrid cross. Monohybrid cross involves research on one characteristic at a time, such as height, which could either be tall or dwarf. Mendel crossed a pure-breeding tall pea plant with a pure-breeding dwarf pea plant. The genotype of a pure-breeding tall plant can be represented as “TT” in the previous generations. The genotype of a pure-breeding dwarf plant can be represented as “tt” in the previous generations. The first generation produced by a cross is called first filial generation (F1) (Figure 5.11). When individuals from F1 are crossed, the second filial generation (F2) is formed (Figure 5.12). Genotype is the genetic information in an organism. Phenotype is the physical characteristics shown in an organism. Gregor Mendel (1822-1884) “Father of Genetics” 5.2.2 Renowned Scientists Figure 5.11 Schematic diagram of monohybrid crossing for height F1 offspring phenotypes : Pure-breeding tall × pea plant Parental phenotypes : Pure-breeding dwarf pea plant tt Meiosis t t Parental genotypes : TT F Tt 1 offspring genotypes : Tt Tt Tt Tall Tall Tall Tall Meiosis Fertilisation Gamete : T T 86
5.2.2 Tall pea plant × Tall pea plant Tt Meiosis T t Tt TT Tt Meiosis T t F2 offspring phenotypes : Parental phenotypes : Parental genotypes : F2 offspring genotypes : Tall Tall Tall Dwarf Fertilisation Gamete : Tt tt Figure 5.12 Schematic diagram of monohybrid crossing of the second filial generation for height The inheritance of characteristics from the Mendel’s experiment can be used to explain the inherited characteristics of humans. The characteristics inherited by a person depend on the genes inherited from his parents. The inheritance mechanism is shown in the schematic diagram below (Figure 5.13). Father (able to roll tongue) × Mother (unable to roll tongue) bb Meiosis b b BB Bb Able to roll tongue Able to roll tongue Able to roll tongue Able to roll tongue Meiosis B B F1 offspring phenotypes : Parental phenotypes : Parental genotypes : F1 offspring genotypes : Fertilisation Gamete : Bb Bb Bb Figure 5.13 Schematic diagram of the inheritance of the ability to roll tongue Genetics Chapter 5 87
Ovum 22 + X Meiosis Sperm 22 + X or 22 + Y Male 44 + XY Photograph 5.4 Chromosome content in human gametes 5.2.2 Female 44 + XX Unlike the inheritance of the ability to roll the tongue as discussed earlier, the inheritance of the sex of a child is determined by the sex chromosomes, received from the parents. In subtopic 5.1, we studied about autosomes and sex chromosomes. A male and a female have 46 chromosomes each which are made up of 44 autosomes and two sex chromosomes. The male has two types of sex chromosomes which are X and Y, while the female has only two X chromosomes. After meiosis, the sperm has only half the number of its parent chromosomes, that is 23 chromosomes (either 22 + X or 22 + Y). The ovum will also have half the number of its parent chromosomes, that is 23 chromosomes (22 + X). The gender of a child depends on the type of sperm that fertilises the ovum. If the sperm (22 + X) fertilises the ovum (22 + X), the gender of the child formed is a female, (44 + XX). If the sperm (22 + Y) fertilises the ovum (22 + X), a male child will be born, (44 + XY). 88
5.2.2 Gender determination of an offspring is shown in Figure 5.14. Figure 5.14 Schematic diagram of determining a child’s gender Based on the figure above, the chances of getting a male or a female offspring at each pregnancy is equal, which is 50%. Parents : Father × Mother 44 + XX Meiosis 22 + X 22 + X Genotype : 44 + XY Offspring genotypes : 44 + XX 44 + XX 44 + XY 44 + XY Gender of offspring : Female Female Male Male Meiosis Fertilisation Gamete : 22 + X Sperm 22 + Y Ovum Formative Practice Formative Practice 5.2 1. Explain the differences between the dominant allele and the recessive allele. 2. What are sex chromosomes? 3. What determines the gender of a child? Explain your answer. Aim: To predict the genotype and phenotype ratio for monohybrid crosses. Instructions: 1. Carry out this activity in groups. 2. Each group is given an incomplete schematic diagram of inheritance for monohybrid cross of a characteristic of the garden pea plant studied by Mendel. 3. Complete the schematic diagram of inheritance. 4. Present the results of your group to the class. ... ... Activity 5.2 Windows Pane 21st Century Skills Genetics Chapter 5 89