Revisi Cepat SPM Biology Form 4 & 5

Penerbit Ilmu Bakti Sdn. Bhd
Coloured Graphical Notes

Biology

FORM

QRCode SPM Model Test Dr Chee Ken Nee
SAMPLE & Answers Hamirizan binti Mohd Ali

(Guru Cemerlang)

Meera Vedan
Lee Shok Mee
Muhamad Ikhwan Mat Saad (PhD)

Form 4Penerbit Ilmu Bakti Sdn. Bhd Form 4

Chapter 1 Introduction to Biology and Laboratory Rules
Meaning of Biology

Biology is the organised study of living things and their life processes in the
natural environment.

Fields and Careers in Biology

Botany – Study of plant life
Genetics – Study of inheritance and genetic variation
Ecology – Study of the interactions between organisms and their environment
Physiology – Study of the functions and mechanisms in organisms
Microbiology – Study of microorganisms
Zoology – Study of animals
Anatomy – Study of the structures of organism body

Medical doctor Scientist Dietician
Nurse Career Research officer
Biotechnologist Botanist
Science teacher Pharmacist
Microbiologist Zoologist
Physiotherapist

N1

Chapter 2 Cell Biology and Organisation
Cell Structure and Function

Animal cell Plant cell

Centriole – Forms Plasma membrane – Controls Chloroplast – Site
spindle fibre substances in and out of the cell for photosynthesis
during cell division
Penerbit Ilmu Bakti Sdn. Bhd
Smooth endoplasmic reticulum Form 4
– Synthesises and transports
glycerol and lipids, and involves
in the detoxification of drugs

Nucleus – Controls cellular
activities and carries genetic
information

Mitochondrion – Site that Vacuole –
generates energy through glucose Maintains
oxidation the turgidity
of the cell
Ribosome – Synthesises protein

Rough endoplasmic reticulum – Transports proteins synthesised by ribosomes

Golgi apparatus – Processes, modifies, Cell wall –
packages and transports protein, carbohydrate Maintains the
and glycoprotein shape of the cell

Cell Organisation in Multicellular Organisms

Cell Tissue Organ System Multicellular
organism
The basic Consists of Consists of Consists
unit of life. a group of a group of of several Consists of
similar cells. different organs that all systems
tissues carry out that carry
that work specific out all the
together. functions. basic life
processes.

N3

Form 5 Bhd

Chapter 1 Organisation of Plant Tissues and Growth
Organisation of Plant Tissues and Zone of Cell Growth

Plant tissues

Meristematic tissues – A Permanent tissues – Non-
group of young cells that has dividing cells that are derived
the ability to divide but has from the meristematic tissues
not undergone differentiation. and completely differentiated.
Sdn.
Apical Lateral Epidermal Ground Vascular
meristematic meristematic tissues
tissues tissues
tissues tissues
Form 5
Cuticle Shoot apical meristems
Bakti
Xylem Epidermal Cork
Phloem cambium

tissue Leaf

Phloem Ilmu Epidermal Stem Lateral Vascular
Xylem tissue Root meristems cambium

Ground Cambium
tissue
Primary
Primary xylem
phloem
Vascular Epidermal
cambium tissue

Ground
tissue
Penerbit Root apical meristems

Zone of cell growth

Shoot apical meristem Matured tissue

Zone of cell Leaf Xylem Zone of cell
division primordium Phloem differentiation

Zone of cell Vascular tissues Root hairs Zone of cell
elongation elongation
start to form Vascular tissues
Zone of cell Xylem start to form Zone of cell division
differentiation Phloem

Matured Cortex Root apical meristem
tissue
Epidermis Root cap

Shoot tip Root tip

N20

Contents

Graphical Notes N1 – N32 4.3 Protein 55

4.4 Lipid 56

4.5 Nucleic Acid 59
Penerbit Ilmu Bakti Sdn. BhdFORM 4
Summative Practice 4 62

Theme 1: Fundamentals of Biology 5Chapter Metabolism and Enzymes 63

1Chapter Introduction to Biology and

Laboratory Rules 1 5.1 Metabolism 63

1.1 Fields and Careers in Biology 1 5.2 Enzymes 63

1.2 Safety and Rules in Biology 5.3 Application of Enzymes in

Laboratory 2 Daily Life 73

1.3 Communication in Biology 7 Summative Practice 5 75

1.4 Scientific Investigation in Chapter

Biology 9 6 Cell Division 76

Summative Practice 1 11 6.1 Cell Division 76

Chapter Cell Biology and 6.2 Cell Cycle and Mitosis 77
Organisation 12
2 6.3 Meiosis 83

2.1 Cell Structure and Function 12 6.4 Issues of Cell Division on
2.2 Living Processes in Unicellular
Human Health 87
Organisms 18
2.3 Living Processes in Multicellular Summative Practice 6 89

Organisms 20 Chapter Cellular Respiration 91
2.4 Levels of Organisation in
7
Multicellular Organisms 27
7.1 Production of Energy through
Summative Practice 2 31
Cellular Respiration 91

7.2 Aerobic Respiration 92

3Chapter Movement of Substances 7.3 Fermentation 94
Across a Plasma Membrane 32
Summative Practice 7 99

3.1 Structure of a Plasma Membrane 32 Theme 2: Physiology of Humans dan Animals

3.2 Concept of Movement of Chapter Respiratory System in
Humans and Animals
Substances Across a Plasma 8 100

Membrane 34

3.3 Movement of Substances Across 8.1 Types of Respiratory System 100
8.2 Mechanism of Breathing 104
a Plasma Membrane in Living 8.3 Gaseous Exchange in Humans 107
8.4 Health Issues Related to the
Organisms 41
Human Respiratory Systems 109
3.4 Movement of Substances Across
Summative Practice 8 110
a Plasma Membrane and its

Application in Daily Life 47

Summative Practice 3 49

Chapter Chemical Compositions 50 Chapter Nutrition and Human 112
in the Cell Digestive System
4 9 112
112
4.1 Water 50 9.1 Digestive System
9.2 Digestion
4.2 Carbohydrate 51

1Chapter Theme 1: Fundamentals of Biology

Introduction to Biology and
Laboratory Rules

Penerbit Ilmu Bakti Sdn. Bhd1.1Fields and Careers in 3 The importance of Biology: CHAPTER 1 FORM 4
Biology (a) To understand the various

Meaning of Biology interactions around us
(b) To understand how the human
1 The word biology is derived from
the Greek words ‘bios’ meaning ‘life’ body functions
and ‘logos’ meaning ‘study’. (c) To find cures for diseases
(d) To save endangered species
2 Biology is defined as the study of life (e) To manage problems related to
and living organisms. An organism
is a living entity consisting of one the environment
cell (for example, a bacterium) or of (f) To treat genetic diseases using
several cells (for example, animals,
plants and fungi). gene therapy
(g) For the advancement in the

fields of medicine, agriculture
and industry

Table 1.1 Description of the major fields of Biology

Major fields of Biology Description
Anatomy The study of the body structures and organisation of organisms
Bacteriology The study of bacteria
Bioinformatics The study of the science of storing, retrieving and analysing
large amounts of biological information
Biotechnology The study of the application of Biology in the industry
Biochemistry The study of the chemical substances and processes that occur
in plants, animals and microorganisms, and of the changes they
Botany undergo during development and life
Cytology The study of plants
Ecology The study of cells
The study of interaction between living organisms and the
Genetics environment
Microbiology The study of genes, genetic variation, and heredity in organisms
Nanobiotechnology The study of microscopic organisms
The study of the application of nanotechnologies in biological
Physiology fields
Taxonomy The study of functions of living organisms and their parts
Zoology The study of classification of organisms
The study of animals

Keywords • Endangered – Terancam • Gene therapy – Terapi gen
• Field – Bidang • Interaction – Interaksi

1

Contribution of Biology in Daily Life QUICK CHECK 1.1

Table 1.2 Contributions of biology in daily life 1 Complete the table below.

Fields Contributions of biology Major fields of Descriptions
Biology
Health • Coming up with measures
and for preventing diseases (a) Microbiology
medicine
• Formulating drugs to Bakti Sdn. Bhd
CHAPTER 1 FORM 4 fight disease-causing (b) The study of the
microorganisms application of
nanotechnologies
• Gene therapy in biological
• Plastic surgery fields
• In vitro fertilisation
• Production of vaccine and (c) Physiology

insulin

Agriculture • High-yielding and pest- (d) The study of
resistant varieties of crops classification of
organisms
• Hydroponic and
aeroponic technology

Food Microbes are used to aid in (e) Zoology

production the making of dairy products
such as curd, cheese, yoghurt,
tapai and tempe 2 State three types of careers related to
agriculture.

Careers Related to Biology 1.2 Safety and Rules in
Biology Laboratory
Table 1.3 shows the examples of careers
related to the fields of Biology. Self-Protective Equipment and their

Table 1.3 Careers related to the fields of Biology Functions
u
Fields 1 Laboratory coat
Penerbit Ilm Careers (a) Laboratory coat should be

Health and Medical doctor, nurse, worn to protect the student’s
medicine physiotherapist, body and clothing from coming
pharmacist, dentist, into contact with hazardous
veterinarian, scientist, chemical substances.
microbiologist, forensic (b) Students must wear approved
scientist laboratory coats completely
buttoned in laboratories at all
Biotechnology Biotechnologist, food times.
technologist (c) Laboratory coats are not to be
worn outside of the laboratories,
Agriculture Botanist, research especially in public areas such
officer, fishery officer, as the canteen to avoid cross-
horticulture officer, contamination.
agriculture officer,
forestry officer

Industry Nutritionist, dietician,
scientist

Keywords • Laboratory coat – Baju makmal
• Fields and careers – Bidang dan kerjaya

2

2Chapter Theme 1: Fundamentals of Biology

Cell Biology and Organisation

CHAPTER 2 FORM 4 2.1 Cell Structure and Function Bakti Sdn. Bhd

1 Cells are the basic unit of life.
2 Cells are often referred to as the building blocks of life.
3 We can study the structure of animal and plant cells through a light microscope.

Preparation of Microscope Slides of Plant and Animal Cells and Identifying
Their Structures

Experiment 2.1

Aim: u 1 A piece of onion scale (roughly
Penerbit Ilm To prepare the slides of plant and animal 1 cm × 1 cm) is cut from an onion
cells and observe their structures bulb using a scalpel.
Materials:
Onion bulb, iodine solution, distilled water, 2 The transparent epidermis from the
methylene blue solution, cheek cells, filter inner surface of the onion scale leaf
papers is gently peeled off using a pair of
Apparatus: forceps. [Refer Diagram 2.1(a)]
Light microscope, glass slides, cover slips, a
pair of forceps, scalpel, dropper, mounting 3 A drop of water is put on the glass
needle, toothpick slide and the epidermis is placed on
top of the water droplet.
Technique:
Prepare and stain wet mount of specimens. 4 With the help of a mounting needle,
Observe the specimen under the light the specimen is covered with a cover
microscope and draw the structures of the slip at an angle of 45o.
plant and animal cells.
Procedure: [Refer Diagram 2.1(b)]
A Preparing and studying slide of plant
Diagram 2.1 (b)
cells
5 A drop of iodine solution is placed
Diagram 2.1 (a) onto one end of the cover slip. A
filter paper is placed at the opposite
end of the cover slip to allow the
iodine solution to spread through
the epidermis to stain the cells. This
technique is called the irrigation
technique.

Keywords • Structure – Struktur
• Cell – Sel

12

6 A piece of filter paper is used to Cell wall Cytoplasm
absorb the excess iodine solution. Vacuole

7 The slide is observed under a light Cell Nucleus
microscope using the low powered- membrane
lens, followed by the high-powered
lens. (b)
Diagram 2.2 (a) Under light microscope,
8 What is observed under the
microscope is drawn and labelled. (b) drawing of one plant cell
The magnification used is recorded.
Penerbit Ilmu Bakti Sdn. Bhd Animal cells observed under light CHAPTER 2 FORM 4
B Preparing and studying slide of microscope
animal cells
Cell membrane
1 The inside of the cheek is gently
scraped with the blunt end of a Nucleus
toothpick.
Cytoplasm
2 The cheek extract is mounted on a (Magnification: x 400)
slide with a drop of water.
(a)
3 With the help of a long needle,
a cover slide is lowered onto the Cell membrane
specimen, making sure there are no Nucleus
air bubbles trapped under the cover
slip. Cytoplasm

4 A drop of methylene blue solution (b)
is placed onto one end of the cover Diagram 2.3 (a) Under light microscope,
slip. A filter paper is placed at the
opposite end of the cover slip to (b) drawing of one animal cell
allow the methylene blue solution
to spread through the cheek extract Discussion:
to stain the cells. This technique is 1 Plant cells have a fixed shape.
called the irrigation technique. 2 The colour of the nucleus in the plant

5 The slide is observed under the light cell that is stained with iodine solution
microscope using the low-powered is yellow.
lens, followed by the high-powered 3 Human cheek cells do not have fixed
lens. shape.
4 The colour of the cytoplasm and
6 What is observed under the light nucleus in the human cheek cell that
microscope is drawn and labelled. are stained with the methylene blue
The magnification used is recorded. solution is blue.
5 The cell structures that can be
Observations: observed under the light microscope
Plant cells observed under light for both the plant and animal cells
microscope are the nucleus and cytoplasm. The
structure that is present in the onion
Cell wall cell which is the cell wall is not present
in the human cheek cell. Onion cells do
Nucleus not contain chloroplasts.
Cytoplasm 6 If a plant cell that carries out
photosynthesis is observed under
(Magnification: x 400) the light microscope, for example cells
(a) from Hydrilla sp. leaf, chloroplasts can
be seen.

Conclusion:

Plant and animal cells have similarities and
differences.

13

Extracellular fluid Na+ Na+ Na+ Na+ Na+
Na+ Na+ Na+
Na+ Na+
Na+ Na+ Na+ Na+
NaN+a+ Na+ Na+ Na+
Na+ NaN+ a+Na+

Na+

Na+ Na+
Na+
Cytoplasm Na+ Binding site of Na+ ATP
Na+ carrier protein
P
Na+ ADP
Bakti Sdn. Bhd
CHAPTER 3 FORM 4 Na+ ions bind to theNa+ ATP
binding site of the carrier ATP (adenosine triphospPhate) is split into ADP
and phosphate. The splittinAgDoPf ATP releases

protein in the cell. energy to the carrier protein. The phosphate

group attaches itself to the carrier protein.

Na+ Na+ Na+ Na+

Na+ NaN+a+Na+Na+NaN+ a+

Extracellular fluid Na+ Na+ Na+ Released to the other
Na+ side of the membrane

Na+

P

Cytoplasm P

The energy from the ATP changes the The carrier protein returns
shape of the carrier protein. The carrier to its original shape.
protein releases the Na+ ions to the
outside of the cell.

Diagram 3.11 Mechanism of active transport for sodium ions

Comparison between Passive and Active Transports
u
Table 3.1 Comparison between passive and active transports
Penerbit Ilm
Similarities

• Both transport substances across the plasma membrane.
• Both occur across the selectively permeable membrane.

Differences

Passive transport Aspect Active transport

Down the concentration gradient Direction of movement Against the
of solute molecules concentration gradient

Does not require energy from the Energy requirement Requires energy from
cell for movement of the cell
molecules

Non-polar and small molecules How are molecules Molecules require the
move easily across the membrane transported assistance of carrier
and do not require assistance protein
whereas polar and large molecules across the plasma
require the assistance of pore or membrane
carrier proteins to move across the
membrane

40

1 The breathing of fish is aided by Breathing Mechanism in Humans
ventilation, produced by the action
of the mouth and the operculum. 1 The breathing mechanism in
humans involves moving air rich
2 The opening and closing of the in oxygen from the environment
operculum allow water to enter the into the lungs and removing air
mouth and then flow over the gills. containing mostly carbon dioxide
from the lungs.
3 The breathing mechanism of fish is
as explained in Table 8.3. 2 The breathing mechanism of
humans is as explained in Table 8.4.
CHAPTER 8 FORM 4 Bakti Sdn. Bhd
Table 8.4 Inhalation and exhalation processes in humans

Inhalation Exhalation

Air flow in Air flow out

Diaphragm lowers Diaphragm returns
and flattens to its original shape

1 External intercostal muscles contractu 1 External intercostal muscles relax
while internal intercostal muscles while internal intercostal muscles
relax. contract.

2 This causes the ribcage to move 2 This causes the ribcage to move
upwards and outwards. downwards and inwards.

3 The diaphragm muscles contract and 3 The diaphragm muscles relax and the
the diaphragm lowers and flattens. diaphragm curves upwards (dome-
shaped).
4 Volume of the thoracic cavity
increases, resulting in reduced air 4 Volume of the thoracic cavity
pressure in the thoracic cavity. decreases, resulting in higher air
pressure in the thoracic cavity.
5 Higher atmospheric pressure outside
forces air into the lungs. 5 Air is forced out of the lungs.
Penerbit Ilm
Dynamic Info

Nasal cavity Pharynx Larynx

Trachea Bronchus Bronchiole Alveolus

The passage of the air we inhale

106

9Chapter Theme 2: Physiology of Humans and Animals

Nutrition and the Human
Digestive System

CHAPTER 9 FORM 4 9.1 Digestive System Bakti Sdn. Bhd9.2 Digestion

Structures of the Human Digestive u Types of Digestion
Penerbit Ilm System
1 Digestion is an important process
1 The digestive system consists of which involves the breaking down of
(a) alimentary canal large food particles into smaller and
(b) accessory organs such as the simpler molecules, which are soluble
and ready to be absorbed by the
liver, gallbladder and pancreas body cells.
2 The alimentary canal also
2 Digestion involves two processes:
known as the digestive tract or (a) Physical digestion
gastrointestinal (GI) tract, is a long (i) Physical digestion is
muscular tube that extends from
the mouth to the anus. It includes the breakdown of food
the mouth, oesophagus, stomach, mechanically driven by
small intestine, large intestine and teeth.
anus. The tongue and teeth are (ii) It includes chewing
structures found in the mouth. (mastication) and
3 The salivary gland, gastric gland peristalsis.
and intestinal glands play a major (b) Chemical digestion
role in digestion by secreting (i) Chemical digestion is the
digestive juices into the digestive breakdown of complex
tract. molecules of food into
simpler molecules.
QUICK CHECK 9.1 (ii) It is driven by enzymes.

1 Name the parts in an alimentary Salivary glands Mouth
canal.
Liver Pharynx
2 Name the organs known as the Oesophagus
accessory organs in the digestive
system. Gallbladder Stomach
Pancreas
3 Underline the correct answer. Duodenum
Intestinal, salivary and (pituitary, Large intestine Small intestine
gastric) glands are the three glands (colon) Anus
that secrete digestive juices into the
alimentary canal. Appendix
Rectum

Diagram 9.1 The human digestive system

Keywords • Gallbladder – Pundi hempedu

• Alimentary canal – Salur alimentari
• Gastric gland – Kelenjar gaster

112

Flow Map

Mouth Oesophagus Stomach

Small intestine Large intestine Rectum

Diagram 9.2 The pathway of food through the alimentary canal

Digestion of Carbohydrates, Proteins and Lipids

1 The digestive process starts in the mouth when we eat and ends in the smallPenerbit Ilmu Bakti Sdn. BhdCHAPTER 9 FORM 4
intestine.

2 The alimentary canal is made up of a series of muscles that coordinate the
movement of food and other cells that make enzymes to digest food.

3 Table 9.1 shows the digestive processes that occur in the mouth, stomach and
small intestine.

Table 9.1 Digestive processes of carbohydrates, proteins and lipids

Location Digestive processes
Mouth
• Presence of food in the mouth stimulates the secretion of saliva by the
salivary glands.

• Salivary amylase hydrolyses starch into maltose.

salivary amylase (pH 6.5 –7.5) maltose
Starch + water

Stomach • With the help of the saliva, the chewed food forms a bolus before being
swallowed.

• The epiglottis closes off the trachea so that food does not enter the
respiratory tract to prevent choking.

• The bolus enters the oesophagus, which is a muscular tube lined with
epithelial cells and mucous glands.

• Mucus lubricates the bolus and reduces friction.
• Through peristalsis, which is a wave-like muscle contractions of the

oesophagus, the bolus is moved along the oesophagus before entering
the stomach.
• The stomach is a muscular, sac-like organ attached to the lower end of
the oesophagus.
• The epithelial lining of the stomach contains gastric glands.
• There are several types of epithelial cells covering the surface of the
stomach:
– Mucous cells secrete an alkaline mucus
– Parietal cells secrete hydrochloric acid
– Chief cells secrete pepsinogen, which is then converted by gastric

acid to the enzyme called pepsin
• Pepsin breaks down protein into polypeptides.

Protein + water pepsin polypeptides

• Hydrochloric acid destroys bacteria in the food and prepares an
environment with the right pH (pH 1.5 – 2.0) for the enzyme pepsin to
react.

• Mucus protects the epithelial lining against acid and digestive enzymes
reactions.

• Peristaltic contractions of the muscular stomach wall mix food with
gastric juice to form a semi-fluid content called chyme. From here, food
moves to the small intestine.

113

Duodenum • The chyme enters the duodenum, which is the first section of the small
(small intestine.
intestine)
• The secretion from gallbladder (bile) and pancreas (pancreatic juice)
enters the duodenum as well and the digestion process continues.

• Pancreatic juice which contains the enzymes pancreatic amylase,
trypsin and lipase is secreted by the pancreas into the duodenum
through the pancreatic duct.

CHAPTER 9 FORM 4 Starch + water pancreatic amylase maltoseBakti Sdn. Bhd
Polypeptide + water trypsin peptides
Lipid + water lipase glycerol + fatty acids

• Bile, an alkaline greenish-yellow liquid produced by the liver and stored
in the gallbladder enters the duodenum through the bile duct.

• Bile prepares an ideal alkaline environment (pH 7.6 – 8.6) for the enzyme
reactions in the duodenum, neutralises the acidic chyme and emulsifies
lipids into smaller droplets to increase the surface area for enzymes to
react.

Jejunum • Jejunum is the second section of the small intestine and ileum is the
and ileum final and longest section of the small intestine.
(small
intestine) • Intestinal juice which contains digestive enzymes is secreted by the
glands in the intestinal walls to complete the digestion of peptides and
disaccharides.

Digestion of proteins:
Peptides + water erepsin amino acids
u
Digestion of carbohydrates:

Penerbit Ilm Maltose + water maltase glucose
Sucrose + water sucrase glucose + fructose
Lactose + water lactase glucose + galactose

Digestion of lipids: lipase glycerol + fatty acids
Lipid + water

• Finally, the digested food molecules will be absorbed through the
intestinal walls into the bloodstream. Undigested food particles will then
be passed on to the large intestine.

Dynamic Info

Although an empty stomach is only about the size of the fist, it can expand to hold up to
4 litres of food and fluid, or more than 75 times the volume of the empty stomach, before
returning to its size when empty.

114

1Chapter Theme 1: Physiology of Flowering Plants

Organisation of Plant Tissues
and Growth

Penerbit Ilmu Bakti Sdn. Bhd1.1Organisation of Plant 4 Matured cells in a permanent tissue
Tissues are derived from the differentiation
of meristematic cells, which
Meristematic and Permanent Tissues
in Plants are modified to perform specific

1 A tissue is made up of a group of functions in plants.
identical cells doing a specific
function. Permanent Tissues

2 Plant tissues are basically classified 1 Permanent tissues are found
into two categories: throughout the plant body and
made up of cells that do not divide,
(a) Meristematic tissues (dividing) they are completely differentiated.
(b) Permanent tissues (non-
2 The cells in the permanent tissues
dividing) depending on the have attained definite shape and
ability of cell division size. Large vacuoles are also present
inside these cells.
Tree Map
3 The permanent tissues in plants
Plant tissue mainly provide support and
protection as well as carrying out
Meristematic tissues Permanent tissues photosynthesis and transporting
water, minerals and nutrients.
Apical Lateral
meristematic meristematic 4 The permanent tissues can be
classified into:
tissues tissues
(a) epidermal tissues
Epidermal Ground Vascular (b) ground tissues
tissues tissues tissues (c) vascular tissues

Parenchyma Collenchyma Sclerenchyma Epidermal tissues Ground tissues
tissues tissues tissues
Leaf

Vascular tissues

Xylem Phloem Stem Epidermal tissues
tissues tissues Ground tissues

Diagram 1.1 Tissue organisation in plants Vascular tissues

3 Meristems give rise to various Root Epidermal tissues
tissues and structures or organs of Ground tissues
a plant, hence ensuring the growth
of the plant. Vascular tissues
Diagram 1.2 Permanent tissues in a plant

Keywords • Permanent tissue – Tisu kekal
• Meristematic tissue – Tisu meristem

222

Structure of a Chloroplast 9 A thylakoid has a flattened disk
shape. Inside it, is the thylakoid
Outer Granum space enveloping a central aqueous
membrane region known as the thylakoid
Lumen lumen.

10 The thylakoid lumen contains
protein complexes and light-
absorbing pigments, such as
chlorophyll and carotenoids.

11 This complex structure is able to
capture light energy from many
wavelengths because chlorophyll
and carotenoids are able to absorb
different wavelengths of light for
photosynthesis.
InnerPenerbit Ilmu Bakti Sdn. BhdStroma
membrane
Thylakoids

Diagram 2.19 Internal structure of a chloroplast

1 Chloroplast is an organelle that Light-dependent Reaction and Light- CHAPTER 2 FORM 5
contains chlorophyll and found independent Reaction

in the cells of plants and green Photosynthesis

algae. A chloroplast is roughly 1–2 1 Photosynthesis is the process of

μm (1 μm = 0.001 mm) thick and synthesising organic compounds
5–7 μm in diameter.
2 In plants, chloroplasts occur in all from inorganic materials using
light energy trapped by chlorophyll.
green tissues that contain pigments, 2 The raw inorganic materials are
water and carbon dioxide and
chlorophyll a and chlorophyll b. the products of photosynthesis are
3 It is the site of photosynthesis,
organic compounds consisting of
the process by which light energy mainly simple sugars and oxygen
as the by-product.
is converted to chemical energy, 3 The process is commonly expressed
in an equation as shown below:
resulting in the production of
oxygen and energy-rich organic 6CO2 Chloroplast C6H12O6
compounds. + Sunlight +
4 A chloroplast is enclosed by an energy
inner and an outer phospholipid 12H2O 6O2
+
membrane.
5 Between these two layers is the 6H2O

intermembrane space. Keywords:
6 The fluid filling up the inner
CO2 = Carbon dioxide
space of the chloroplast is called H2O = Water
the stroma and it contains one or C6H12O6 = Glucose
O2 = Oxygen
more molecules of small, circular
DNA together with ribosomes. Diagram 2.20 Chemical reaction for photosynthesis
7 Within the stroma are stacks
of thylakoids, where photosynthesis

actually takes place.
8 The thylakoids are arranged in

stacks called grana (singular:

granum).

263

4 The process of photosynthesis the chlorophyll molecules become
occurs in two stages: activated, causing electrons to be
promoted to a higher energy level
(a) Light-dependent, or light and released from the chlorophyll
reaction molecules.
4 These electrons will pass through
(b) Light-independent, or dark a series of electron carriers. The
reaction energy from these electrons will be
used to produce energy in the form
5 The light reaction takes place in of ATP.
the thylakoid membranes of the 5 Meanwhile, light energy is also used
chloroplast while the dark reaction to split water molecules, causing
takes place in the stroma of the photolysis. The breaking up of
chloroplast. water releases oxygen, electrons and
protons or H+ (hydrogen ions).
6 The light-dependent reaction uses Bakti Sdn. Bhd
light energy to make two molecules 2H2O 4H+ + 4e- + O2
needed for the next stage of
CHAPTER 2 FORM 5 photosynthesis: 6 During the process, electrons
enter the chlorophyll to replace
u (a) energy storage molecule, ATP those that have been released
Penerbit Ilm (b) reduced electron carrier, from the chlorophyll molecules.
The replacement of the electrons
NADPH enables chlorophyll to respond to
7 The dark reaction of photosynthesis other light energy.

is an intricate process where 7 Each hydrogen ion receives
NADPH and ATP are used to an electron released from the
produce carbohydrate molecules chlorophyll and forms a hydrogen
(or sugars). atom.

Light-dependent reaction H+ + e H
4H+ + 4e 4H
1 The light reaction takes place in
the thylakoid membranes of the 8 Hydrogen from water and electrons
chloroplast. The reactions use from chlorophyll molecules are
light energy to make two molecules: transferred to an acceptor called
NADP+ to form NADPH, which
(a) energy storage molecule, ATP temporarily stores the energised
(b) reduced electron carrier, electrons.

NADPH 9 The products from the light reaction
[Note: NADPH = Nicotinamide are ATP, hydrogen atoms and
oxygen. Oxygen is released as a by-
adenine dinucleotide phosphate product.
hydrogen; ATP = Adenosine
triphosphate]. These two molecules 10 The ATP and hydrogen atoms are
are needed for the next stage of stored in the chloroplast.
photosynthesis.
2 The energy needed for
photosynthesis is obtained from
light, sunlight or artificial light.
This energy is stored in the form
of ATP and used to carry out
photosynthesis.
3 Light is absorbed by the chlorophyll
in chloroplasts. With added energy,

264

1 A leafy twig is cut from a plant and 3 One half of the stem is placed into
then inserted into a rubber tubing the beaker containing plain water
attached to a pipette, which is filled and the other half of the stem is
with water by suction. palced into the beaker containing
red dye.
2 The nozzle end of the pipette is
immersed in the beaker filled with Bakti Sdn. BhdColouredPlain
water. The initial level of coloured water water
water in the beaker is marked. The
CHAPTER 4 FORM 5 apparatus is put under the sunlight Diagram 4.12 Experiment to show xylem vessels
for about one hour. taking up water
u
Penerbit Ilm 3 After an hour, the level of the 4 After an hour, it is observed that
coloured water is marked again. It the portion of the stem in red dye
shows that the level of coloured is stained with red lines, the leaf
water in the pipette has increased. veins are also stained in red as well
as half of the flower.
4 The increase in the level of coloured
coloured water shows that water has 5 The other half of the stem was
been pulled upwards the pipette not stained because plain water is
by a ‘suction force’, which is called passing through the stem.
transpirational pull. This is the
force that causes the movement of Guttation in Plants
water column upwards.
1 Guttation is the process of secretion
5 The suction force occurs when of water droplets from the tips
transpiration is taking place or edges of the leaves of plants
through the leaves. without involving the stomata.

6 As a conclusion, the transpiration 2 It happens in herbaceous plants that
process is responsible in the have vascular systems, such as grass,
movement of water from the leaves hibiscus, maize, tomato, tapioca,
to the atmosphere. It is also the main sweet potato and other small plants.
force that drives the movement of
water from the soil up to the stem. 3 Guttation is not dew droplets that
condense from the atmosphere
Scan QR code or visit onto the plant surface in the cool
https://www.youtube.com/ morning.
watch?v=VMGGAc6sXhs to
watch video on experiment to 4 Since guttation relies on root
demonstrate transpirational pull. pressure, it cannot occur in large
plants, such as trees because the
For educational purposes only pressure required to force water out
from the leaves is too large.
Experiment to examine water uptake

by the stem

1 A beaker is filled with plain water
and another one with water stained
with a few drops of eosin or red dye.

2 The stem with a white flower, such
as a balsam plant is carefully cut
lengthwise part way up the stem.

298

QUICK CHECK 5.2

1 What are the five major phytohormones?
2 Name one major function for each of the phytohormones.
3 Explain briefly how auxins affect the plant growth.

Penerbit Ilmu Bakti Sdn. BhdSummative Practice 5

1 Study the following statement. 3 Which of the following are true
about auxin?
It plays a key role in plant I Promotes germination
development and growth II Promotes fruit ripening
especially in response to I II Enhances apical dominance
tropisms. IV Synthetic auxin is used as weed
killer
Which of the following A I and II CHAPTER 5 FORM 5
B I and III
phytohormones is referred above? C II and IV
A Auxin D III and IV
B Cytokinin
C Ethylene 4 Which of the following statements
D Abscisic acid is correct about the phytohormone
gibberellins?
2 The information below shows the A They are produced during
phytohormones and their functions. formation of fruits
B They break the dormancy of
Which of the following pairs are seeds and buds
matched correctly? C They inhibit the fall of leaves
and fruits
Hormone Function D They are used for the ripening
of fruits
I Abscisic Promotes seed
acid dormancy 5 The English phrase “one bad apple
spoils the bunch!” is referred to
II Cytokinin Delays A eating an apple a day will keep
senescence the doctors away
III Ethylene B one rotten fruit will spoil all the
Closes plant fruits in a basket
IV Gibberellin stomata C ripe fruits produce more ethylene
during water gas causing more fruits to ripe
shortages D fruit ripening is hastened by
removing it from the parent
Promotes fruit plant to cut off the influence
ripening of auxins

A I and II
B I and III
C II and IV
D III and IV

319

6 Which of the following is true about 9 Diagram 3 shows the responses in
ethylene as a phytohormone?
I Circulates in gaseous form shoots P and Q and root R.
II Promotes fruit ripening
I II Causes seed dormancy Light Light
IV Stimulates seed germination
A I and II B I and III Auxin Auxin Root
C II and IV D III and IV Shoot Shoot

Auxin

P QR
% Inhibition % Stimulation Bakti Sdn. Bhd
Diagram 3

7 Diagram 1 shows four coleoptiles Which of the following conclusions
of maize seedlings that have been is correct?
treated differently. A Both the plant shoots and root
require light to produce auxin
Direction of light B Both the plant shoots and
root are showing negative
Aluminium phototropism
cap C High concentration of auxin
stimulates cell elongation in
Agar both the shoot and root
block D High concentration of auxin
inhibits cell elongation in
CHAPTER 5 FORM 5 WX Y Z the root but promotes cell
elongation in the shoot
Diagram 1

Which coleoptiles would show
positive phototropism after two

days? 10 Diagram 4 shows the effect of
A W, X and Y C X and Y various concentrations of auxin on
B X, Y and Z D Y and Z the growth of shoot and root of a
hibiscus plant.
8 An agar block is used to collect
auxin from a cut coleoptile as shownu 200
in Diagram 2. Then, the agar block

is transferred to a cut shoot.
Penerbit Ilm 100 Shoot
Light 0 103 103 103
Concentration
Coleoptile end of auxin

103 103 (mg/dm3)
Root

Cut Diagram 4
shoot
Based on the graph shown in
Agar block Diagram 4, choose the most suitable
conclusion for the experiment.
Diagram 2 A Too much of auxin can reduce
the growth rate of the root only
Which of the following is the possible B Shoot needs more auxin than the
root to obtain maximum growth
observation of the experiment? C Same concentration of auxin is
required for maximum growth
A C of the shoot and root
D In the absence of sunlight,
B D the growth of both the shoot
and root is not affected by the
concentration of auxin

320

Answers

FORM 4 2 Chloroplasts, cell wall and large vacuole
3 Cellulose
1Chapter Introduction to Biology 4 Generate energy in the form of adenosine
and Laboratory Rules
triphosphate (ATP)
Penerbit Ilmu Bakti Sdn. BhdQuick Check 1.1
  1 (a) The study of microscopic organisms Quick Check 2.2
(b) Nanobiotechnology 1 (a) Living thing that made up of one cell.
(c) The study of functions of living (b) Protozoa (Amoeba sp., Paramecium sp.)/

organisms and their parts Fungi (yeast)
(d) Taxonomy Excess water in the cytoplasm diffuses
(e) The study of animals
2 Botanist, research officer, fishery officer into the contractile vacuole which
stores the water before releasing it into
Quick Check 1.2 the surroundings.
1 Glass splinters, rubber fragments 2 Binary fission
2 (a) Malaysian Biosafety and Biosecurity 3 – Pseudopodium is a temporary extension
of the cell membrane of an organism.
Association (MBBA). – Cilia are permanent, short, hair-like
(b) National Institute for Occupational structure that protrudes from an
organism’s cell membrane.
Safety and Health (NIOSH).
Quick Check 2.3
Quick Check 1.3 1 Red blood cells have biconcave shape, in
1 Accurate, not artistically shaded, labelled,
which both sides of their surface curve
label lines not crossed, title given and size inwards enabling the cells to manoeuvre
of structures must be proportionate to each through tiny blood vessel.
other 2 Meristematic cells are actively dividing cells,
2 A: cross section; thus they require a lot of energy.
B: longitudinal section 3 Tay-Sachs

Quick Check 1.4 Quick Check 2.4
1 Identifying a problem
2 Tables, graphs or diagrams 1 (a) Cell (d) Organ
3 (a) Hypothesis
(b) Variables (b) Organ (e) System
(c) Responding
(d) Constant (c) Cell (f) Tissue

Summative Practice 1 2 Cell → Tissue → Organ → System

 1 D  2 D  3 D  4 D Summative Practice 2
 5 D  6 C  7 D
 1 D  2 D  3 B  4 B
2Chapter Cell Biology and  5 A  6 C  7 A
Organisation
3Chapter Movement of Substances
Quick Check 2.1 Across a Plasma
1 Cell
Membrane

Quick Check 3.1
1 Living cells require substances such as

nutrients and oxygen to carry out life
processes and dispose waste products such as
urea and carbon dioxide through the plasma
membrane.

415