Revision Pack
BSB
IGCSE Biology
SECTION 3: Plant Physiology
Term 2/5
approx 16 lessons
Instructions
• You can use the following statements for your
revision. They are taken directly from the
specification.
• They key terms are also listed. Your revision
should enable you to recognise and use these
key terms in the test.
Trigger Words
• Trigger words at the start of the statements
give you an idea of what it is that you might
be asked to do in an exam question
• You can compare these to the exam glossary
that makes up the last two slides of this pack
Important trigger words for IGCSE
Easy
Recognise
Trigger Words
Recall
Describe
Explain
Hard
Understand
Evaluate
Movement of substances into and out
of cells
2.12 recall simple definitions of diffusion,
osmosis and active transport
2.13 understand that movement of substances
into and out of cells can be by diffusion,
osmosis and active transport
Movement of substances into and out
of cells
Diffusion
Osmosis
Active transport
Movement of substances into and out
of cells
2.16 describe simple experiments on diffusion and
osmosis using living and non-living systems.
2.15 understand the factors that affect the rate of
movement of substances into and out of cells to
include the effects of surface area to volume
ratio, temperature and concentration gradient
2.14 understand the importance in plants of turgid
cells as a means of support
Movement of substances into and out
of cells
Diffusion
Osmosis
Living system
Non-living system
Rate
Surface area to volume ratio
Temperature
Concentration gradient
Turgid
Support
Nutrition
2.17 describe the process of photosynthesis and
understand its importance in conversion of
light energy to chemical energy
2.18 recall the word equation and the balanced
chemical symbol equation for photosynthesis
Nutrition
Photosynthesis
Light
Chemical energy
Word equation
Balanced chemical symbol equation
Nutrition
2.22 describe simple controlled experiments to
investigate photosynthesis, showing the
evolution of oxygen from a water plant, the
production of starch and the requirements of
light, carbon dioxide and chlorophyll
Nutrition
Simple controlled experiments
Photosynthesis
Evolution of oxygen
Water plant
Starch
Light
Carbon dioxide
Chlorophyll
Nutrition
2.19 understand how carbon dioxide
concentration, light intensity and temperature
affect the rate of photosynthesis
Nutrition
Carbon dioxide
Concentration
Light intensity
Temperature
Rate of photosynthesis
Gas exchange
2.39 understand gas exchange (of carbon dioxide and
oxygen) in relation to respiration and photosynthesis
2.41 explain how the structure of the leaf is adapted for
gas exchange
2.20 explain how the structure of the leaf is adapted for
photosynthesis
2.43 describe simple controlled experiments to
investigate the effect of light on net gas exchange
from a leaf, using hydrogen-carbonate indicator
2.40 understand that respiration continues during the
day and night, but that the net exchange of carbon
dioxide and oxygen depends on the intensity of light
Gas exchange
Gas exchange
Carbon dioxide
Oxygen
Respiration
Photosynthesis
Structure
Leaf
Adapted
Effect
Light
Net gas exchange
Hydrogen-carbonate indicator
Light intensity
Gas Exchange
2.42 describe the role of stomata in gas
exchange
Excretion
2.67 recall the origin of carbon dioxide and
oxygen as waste products of metabolism and
their loss from the stomata of a leaf
Gas Exchange
Stomata
Gas exchange
Excretion
Carbon dioxide
Oxygen
Waste products
Metabolism
Transport
2.53 explain how water is absorbed by root hair
cells
2.52 describe the role of the xylem in
transporting water and mineral salts from the
roots to other parts of the plant
2.51 describe the role of phloem in
transporting sucrose and amino acids
between the leaves and other parts of the
plant
Transport
Water
Absorbed
Root hair cell
Xylem
Mineral salts
Roots
Phloem
Sucrose
Amino acids
Leaves
Transport
2.54 recall that transpiration is the evaporation
of water from the surface of a plant
2.55 explain how the rate of transpiration is
affected by changes in humidity, wind speed,
temperature and light intensity
2.56 describe experiments that investigate the
role of environmental factors in determining
the rate of transpiration from a leafy shoot
Transport
Transpiration
Evaporation
Water
Rate
Humidity
Wind speed
Temperature
Light intensity
Environmental factors
Nutrition
2.21 recall that plants require mineral ions for
growth and that magnesium ions are needed
for chlorophyll and nitrate ions are needed for
amino acids
Nutrition
Mineral ions
Growth
Magnesium ions
Chlorophyll
Nitrate ions
Amino acids
Coordination and response
2.79 understand that plants respond to stimuli
2.80 describe the geotropic responses of roots
and stems
2.81 describe positive phototropism of stems
Coordination and response
Plants
Respond
Stimuli
Geotropic
Roots
Stems
Positive phototropism
Reproduction
3.3 describe the structures of an insectpollinated and a wind-pollinated flower and
explain how each is adapted for pollination
3.4 understand that the growth of the pollen
tube followed by fertilisation leads to seed
and fruit formation
3.8 understand that plants can reproduce
asexually by natural methods (illustrated by
runners) and by artificial methods (illustrated
by cuttings)
Reproduction
Insect-pollinated
Wind-pollinated
Flower
Adapted
Growth
Pollen tube
Fertilisation
Fruit
Asexual reproduction
Runners
Cuttings
Reproduction
3.6 recall the conditions needed for seed
germination
3.7 understand how germinating seeds utilise
food reserves until the seedling can carry out
photosynthesis
Reproduction
Seed
Germination
Food reserves
Photosynthesis
Food production
Crop plants
5.1 describe how glasshouses and polythene
tunnels can be used to increase the yield of
certain crops
5.2 understand the effects on crop yield of
increased carbon dioxide and increased
temperature in glasshouses
Food production
Glasshouse
Polythene tunnel
Yield
Carbon dioxide
Temperature
Food production
5.3 understand the use of fertiliser to increase
crop yield
5.4 understand the reasons for pest control and
the advantages and disadvantages of using
pesticides and biological control with crop
plants
Food production
Fertiliser
Crop yield
Pest control
Pesticide
Biological control
Crop plant