COMBINED SCIENCE STUDY PACK

BIOLOGY REVISION
AQA GCSE Combined Science: Trilogy 8464
Paper Exam Date
Biology Paper 1
4.1 Cell Biology
4.2 Organisation 12th May 2020
4.3 Infection and Response
4.4 Bioenergetics
Biology Paper 2
4.5 Homeostasis and Response
1st June 2020
4.6 Inheritance, Variation and Evolution
4.7 Ecology

Name_____________________________________
 Combined Science Trilogy Revision Booklet

Contents Page

Page Number Contents

2 How to use your study pack
3 GCSE Command Words
Cells and Systems
Cell Structure
Cell Transport
4 Organisation
Bioenergetics
The human nervous system
Homeostasis
Genetics and Evolution
Reproduction
Variation and evolution
36 Development of understanding genetics
and evolution
Classification of living organisms
Interdependence
Adaptations, interdepence and
competition
49 Organisation of an ecosystem
Biodiversity and the effect of human
interaction on ecosystems
Microbes and Health
Human digestive system and enzymes
62 Non-communicable diseases
Discovery and development of drugs
Plant diseases and defence responses

86 Reflections Page

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 Combined Science Trilogy Revision Booklet

How To Use Your Study Pack

This tells you which bit of

the specification you are This is the big idea This is the topic you
studying. If says here if it is a this topic is part of are studying
triple only topic.

1. Try and answer

the questions in
this box.
2. Use your revision
guide to check
your answers and
correct any you
got wrong.
3. Use the revision
guide to help you
Answer the answer the
exam question in questions you
the ‘prove it’ didn’t know.
section to show
you understand
the topic.
You can mark
this bit using the
marking
scheme. This section will help
you prepare for
any questions that
involve maths in
the exam.

2
 Combined Science Trilogy Revision Booklet

GCSE Command Words

Command
Definition Example Question Example Answer
Word
State, give, Short answer only and
State the units for
name, write does not require an m/s2
acceleration.
down explanation.
Place a large number of quadrats
randomly in the field. Count the
Describe how quadrats
Describe Recall facts, events or number of plants in the quadrat.
should be used to
(not graphs process in an accurate Calculate the mean number in each
estimate the number of
or practical) way. quadrat then use the area of the
plants in a field.
quadrat and field to estimate the
number of plants.
Identify the pattern in
Describe the pattern of
the graph and use The percentage of tooth decay
Describe tooth decay in Figure 3
numbers from the increases with age by 4% for each
(graphs) for water without
graph to make this age group in figure 3.
fluoride.
clear.
Measure the rate of reaction by
Plan an experiment to
Write the method for adding a set amount of metal to set
Describe test the hypothesis “the
the practical or the type, volume and concentration of
(practical)/ higher the
results that you would acid and time how long it takes to
Plan temperature, the faster
expect to see. stop fizzing. Repeat the experiment
the rate of reaction”.
at 5 different temperatures.
Determine the half-life
Use given data or of a sample if it
Determine information to obtain decreases from 1000g 1.3 million years
and answer. to 250g in 2.6million
years.
Make something clear
or state the reasons for
something happening. Soot forms during incomplete
Explain You will need to state Explain why soot forms. combustion when not enough
what is happening and oxygen is present.
then say why it
happens.
Paper bags are made from a
Use the information A company stated: ‘A renewable resource whereas plastic
supplied and your own Life Cycle Assessment bags are made from finite resources.
knowledge to consider shows that using plastic However paper bags are bad
the evidence for and bags has less because they produce much more
Evaluate
against a point. You environmental impact solid waste and more CO2 is released
may also be required than using paper when they are produced therefore
to include a justified bags’. Evaluate this the negative impacts of paper bags
conclusion. statement. outweigh the problem of plastic
coming from a finite resource.
Describe the similarities Compare the
and/or differences differences between Cracking involves a catalyst whereas
Compare
between things. Avoid cracking and distillation does not.
writing about just one. distillation.
Sketch a current–
potential difference
Sketch Draw approximately.
graph for a filament
lamp.

3
 Combined Science Trilogy Revision Booklet

Cells and Systems Keywords

Add all the important keywords for this big idea in the grid below
as you come across them in the study pack.

Word Definition

4
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Eukaryotes and prokaryotes
Ref. Ref.
4.1.1.1 Key information:
- Plant and animal cells (eukaryotic cells) have:
- genetic material enclosed in a nucleus to control the activity of the cell
- a cell membrane to control what enters and exits the cell
- cytoplasm to allow reactions to take place
- Bacterial cells (prokaryotic cells) are much smaller in comparison. The genetic
material is not enclosed in a nucleus. It is a single DNA loop and there may be
one or more small rings of DNA called plasmids. They also have cytoplasm, a cell
membrane and a cell wall to provide strength and support to the cell.
1. What type of cells are eukaryotic cells?

2. What type of cells are prokaryotic cells?

3. Outline 3 differences between prokaryotes and eukaryotes.

Maths Skills
MS2h
Size of image (mm) Magnification Size of real object (mm)
5 40
10 1000
12 60
8 200
15 500

How many orders of magnitude bigger is the first sample compared to the second?

5
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Animal and plant cells
Ref. Ref.
Key information:
4.1.1.2 Most animal cells have the following parts:
a nucleus, cytoplasm, a cell membrane, mitochondria to carry out aerobic respiration
which releases energy for the cell, ribosomes to carry out protein synthesis by joining
many amino acids.
In addition to the parts found in animal cells, plant cells often have:
• chloroplasts filled with chlorophyll to absorb light for photosynthesis
• a permanent vacuole filled with cell sap to provide support to the cell
Plant and algal cells also have a cell wall made of cellulose, which strengthens the cell.
1. Label the cells:

2. Fill in the table with the functions of each organelle.

Organelle Function
Nucleus
Cytoplasm
Cell membrane
Mitochondria
Ribosomes
Chloroplasts
Vacuole
Cell wall

3. Identify three organelles found in plant cells but not animal cells.

Prove It!

6
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec. Required practical 1: Use a light microscope to observe, draw and label a selection of
Ref. Ref. plant and animal cells.
Key information:
4.1.1.2 - A light microscope shines a beam of light across a thin, dead, stained specimen.
- The resolution (ability to distinguish between two points) and magnification of a
AT 1 light microscope is high enough the view the nucleus and cell membrane.
and 7 - Most organelles are too small to be viewed with a light microscope.
- When drawing an image from a microscope a pencil must be used. Labels
should
1. The image shows human cheek cells. In the
space below, draw a biological drawing of this
image. Label the organelles which are visible.

WS 1.2

2. Describe how the slide of cheek cells

would have been prepared.

3. State what is meant by the term resolution.

4. Give the equation that links magnification, image size and actual size.

Maths Skills
Ma Convert the following:
1a, 1. 3cm into mm =
1b, 2a 2. 3mm into μm =
3. 50μm into mm =

Put these numbers into standard form:

1. 6 000
2. 400
3. 80 000
4. 0.007

Answer the following questions:

1. A heart muscle cell with a length of 23μm is magnified 200x. What is the image
size? Give your answer in metres in standard form.

2. A root hair cell image is 7.8 cm in length. The image is being magnified 4500x.
Calculate the real length of the object in metres. Giving your answer in standard
form to 3 significant figures.

3. The image of a nerve cell measures 3.5 cm. It has been magnified 3000x.
Calculate the real size of the nerve cell, giving your answer in metres and
standard form.

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 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Cell specialisation
Ref. Ref.
Key information:
4.1.1.3 Cells may be specialised to carry out a particular function:
• sperm cells, nerve cells and muscle cells in animals
• root hair cells, xylem and phloem cells in plants.
NAME PICTURE STRUCTURE FUNCTION
OF CELL
Has a large Allows
PHLOEM surface area electrical
CELLS because of a impulses to
long finger-like pass around
projection the body
ROOT Has a long Transports
HAIR flagella and lots water and
CELL of mitochondria mineral ions
around a
plant
Has a long Fertilises an
NERVE axon and a cell egg cell
CELL body found in
the CNS
Consists of long Absorbs
SPERM hollow tubes water for a
CELL strengthened plant
with lignin
Consists of long Transports
XYLEM hollow tubes dissolved
CELLS sugars
around a
plant
Have hairs on Control
MUSCLE the tops of cells movement of
CELLS to increase the skeleton
surface area in animals

Have lots of Absorb

CILIATED mitochondria nutrients from
CELLS to release extra the small
energy intestine

Prove It!
1. Describe how the structure of a sperm cell relates to its function.

2. Describe how the structure of a root hair cell relates to its function.

3. Describe how the structure of a nerve cell relates to its function.

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 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Cell differentiation
Ref. Ref.
Key information:
4.1.1.4 As an organism develops, cells differentiate to form different types of cells.
• Most types of animal cell differentiate at an early stage.
• Many types of plant cells can differentiate throughout life.
In mature animals, cell division is mainly restricted to repair and replacement. As a cell
differentiates it gets different sub-cellular structures so it can carry out a certain function.
It has become a specialised cell.
1. State what is meant by the term ‘differentiation’.

2. Describe why cell division is important for animals.

3. Give one example of a specialised cell and outline how it is specialised to carry
out its function.

4. State the name of the tissue in plants which allows plant cells to differentiate
throughout life.

Prove It!

9
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Diffusion
Ref. Ref.
Key information:
4.1.3.1 - Diffusion is the spreading out of the particles of any substance in solution, or
particles of a gas, resulting in a net movement from an area of higher
concentration to an area of lower concentration.
1. Define the term ‘diffusion’.

2. Give two examples of molecules which diffuse in and out of cells. Name the
process these molecules are involved in.

3. State three factors that affect the rate of diffusion.

4. Describe the relationship between surface area: volume ratio and the rate of
diffusion.

5. Complete the table to show how the following are adapted for exchanging
materials.

Organ How it is adapted for exchange

Lungs

Small
intestine
Gills

Leaves

Roots

Prove It!

(6)

10
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Osmosis
Ref. Ref.
Key information:
4.1.3.2 Water may move across cell membranes via osmosis.
Osmosis is the diffusion of water from a dilute solution to a concentrated solution
through a partially permeable membrane.
1. Define the term ‘osmosis’.

2.

Prove It!

(3)

11
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec. Required practical 2 (biology: required practical 3): Investigate the effect of a range of
Ref. Ref. concentrations of salt or sugar solutions on the mass of plant tissue.
Key information:
AT 1, - Plant tissue can be used to measure the rate of uptake of water in different
3, 5 solutions.
- During these experiments, only the water moves. Salt and sugar molecules are
too large to pass across the partially permeable membranes.
- The higher the concentration of salt or sugar, the lower the concentration of
water.
1. Describe why the water moves from the
left to the right side.

2. Explain why the sugar molecules do not

move.

Maths Skills
MS1a,
1c

12
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Active transport
Ref. Ref.

Key information:
4.1.3.3
- Active transport moves substances from a more dilute solution to a more
concentrated solution (against a concentration gradient). This requires energy
from respiration.
- Active transport allows mineral ions to be absorbed into plant root hairs from
very dilute solutions in the soil. Plants require ions for healthy growth. It also allows
sugar molecules to be absorbed from lower concentrations in the gut into the
blood which has a higher sugar concentration. Sugar molecules are used for cell
respiration.
1. Outline the main differences between diffusion and active transport.

2. Explain, using examples, the importance of active transport for plant growth.

3. Explain why active transport cannot occur in the absence of oxygen.

4. Describe when active transport is used by the cells lining the small intestine.

Prove It!

13
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Principles of organisation
Ref. Ref.
Key information:
4.2.1 Cells are the basic building blocks of all organisms. A tissue is a group of cells with a
similar structure and function. Organs are aggregations of tissues performing specific
functions. Organs are organised into organ systems, which work together to form
organisms.
1. Put the following in order of size (smallest to largest):
Tissue Organ Cell Organ system

MS 1c ___________  ____________  ______________  __________________

2. Describe the difference between a tissue and an organ.

3. Name the three tissues of the stomach. Give the function of each.

4. Give an example of a plant organ and state its function.

Prove It!

14
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
The heart and blood vessels
Ref. Ref.

Key information:
4.2.2.2
- The heart is an organ that pumps blood around the body in a double circulatory
system. The right ventricle pumps blood to the lungs where gas exchange takes
place. The left ventricle pumps blood around the rest of the body.
- The natural resting heart rate is controlled by a group of cells located in the right
atrium that act as a pacemaker. Artificial pacemakers are electrical devices
used to correct irregularities.
- The three different types of blood vessel are arteries, veins and capillaries.
1. Label the diagram of the heart

2. Describe the passage of blood

through the left hand side of the heart.

3. Explain the importance of valves in

the heart.

4. Name the artery that supplies the

heart with blood. Explain the importance of
the heart having its own blood supply.

5. Where are the group of cells that control the natural resting heart rate found?

6. Outline the difference in the structure of arteries and veins.

7. Describe how the structure of a capillary relates to its function.

Prove It!

15
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
The lungs
Ref. Ref.
Key information:
4.2.2.2 The lungs are specialised organs adapted to allow for efficient gas exchange. They
have a large surface area: volume ratio to ensure that gas exchange can occur at a
high rate.
1. Label the following parts:
Trachea, bronchus, bronchiole, trachea,
alveoli, lung, mouth, nasal cavity

2. Describe how the alveoli are

adapted for efficient gas exchange.

Maths Skills

16
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Blood
Ref. Ref.
Key information:
4.2.2.3 Blood is a tissue consisting of plasma, in which the red blood cells, white blood cells and
platelets are suspended.
1. Describe the function of plasma.

2. Identify the part of the blood which transports oxygen.

3. Describe the role of white blood cells

4. Describe the role of platelets.

5. Explain why blood is described as a tissue.

6. Label the blood cells in this image.

Prove It!
MS1a

17
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Plant tissues
Ref. Ref.
Key information:
4.2.3.1 - Plant tissues include epidermal tissues, palisade mesophyll, spongy mesophyll,
xylem and phloem, and meristem tissue.
- The lead is a plant organ which is adapted in order to carry out photosynthesis.

1. Identify the structures in the cross-sectional diagram of the

leaf.
A=
B=
C=
D=
E=

2. Describe two ways in which the leaf is adapted for photosynthesis.

3. Describe the structure and function of a xylem vessel.

4. Describe the structure and function of a phloem vessel.

Prove It!

18
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Plant organ systems
Ref. Ref.
Key information:
4.2.3.2 Transpiration occurs due to the evaporation of water vapour from the leaves. It is the
movement of water from the roots to the atmosphere via the xylem and leaves.
Xylem vessels and hollow tubes strengthened by lignin. Their role is to transport water in
the transpiration stream.
Phloem tissue is made up of long cells with pores in their ends. Dissolved sugars (sucrose)
travel from the leaves to the rest of the plant for immediate use (in respiration) or for
storage. The movement of sugar through the phloem tissue is called translocation.
1. Label the plant with the plant organs.

2. Describe the passage of water through the plant.

3. Explain how the structure of the root hair cell is

adapted to its function.

4. Plants living in very hot areas have very few stomata on the underside of the
leaf. Explain why.

5. Describe the difference in the structure and function of phloem and xylem
vessels.

6. Complete the table to show the effects of changing conditions on rate of

transpiration:
Condition Change Effect on Rate of Transpiration
Increased temperature
Decreased humidity
Decreased air movement
Increased light intensity
Prove It!

19
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
The stomata
Ref. Ref.
Key information:
4.2.3.2 - The stomata and guard cells are found on the underside of the leaf and are
used to control gas exchange and water loss.
1. Describe how the following equipment could be used to investigate the number
of stomata on the underside of a leaf.
Nail varnish Sticky tape Microscope

2. Suggest why the stomata are closed at night.

Maths Skills
MS
2a,
2b,
2d,

(3)

20
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Photosynthesis – the reaction
Ref. Ref.
Key information:
4.4.1.1 - Photosynthesis is an endothermic reaction in which energy is transferred from the
environment to the chloroplasts by light to produce glucose.
1. Write the word and symbol equation for photosynthesis.

2. Explain why photosynthesis only occurs during the day.

3. Explain why photosynthesis is described as an endothermic reaction.

4. Describe how a leaf is adapted in order to carry out photosynthesis.

Prove It!

21
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
The rate of photosynthesis
Ref. Ref.
Key information:
4.4.1.2 - The rate of photosynthesis can be limited by a number of different factors.
1. Name four factors which limit the rate of photosynthesis.

2. The sketch graph shows the effect of carbon dioxide on photosynthesis.

Describe and explain the shape of the graph.

3. Explain the effect of temperature on the rate of photosynthesis.

Prove It!

(5)

22
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
The rate of photosynthesis (HIGHER TIER ONLY)
Ref. Ref.
Key information:
4.4.1.2 - Farmers and gardeners use their knowledge of limiting factors to design
greenhouses which increase the rate of photosynthesis in plants to ensure profits.
- The intensity of light at different distances from a light source can be described
by the inverse square law. This states that the intensity of light is inversely
proportional to the square of the distance from the source.
1. Give the equation which links light intensity and distance. State the unit for light
MS intensity.
3a, 3d

2. Describe and explain the shape of the graph below.

3. Describe how greenhouses are designed to ensure gardeners are able to

maximise their profits.

Prove It!

23
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec. Required practical 5 (biology: required practical 6): Investigating the effect of light
Ref. Ref. intensity on the rate of photosynthesis using an aquatic organism such as pondweed.
1. Name the equipment needed for this experiment.
4.4.1.2

AT 1, 2. Describe how to change the light intensity. Identify the piece of equipment
2, 3, 4, needed to record light intensity.
5

3. Identify the dependent variable in this investigation. Suggest how this is

measured.
WS2.2

4. Name two control variables. Describe how you would ensure these variables are
kept constant.

5. How are the dependent variable and one of the control variables used to
calculate rate?

Prove It!

24
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Uses of glucose from photosynthesis
Ref. Ref.
Key information:
4.4.1.3 - The glucose produced in photosynthesis is required by plants for a number of
processes. It is often converted into different molecules required for plant
survival.
- Plants require nitrate ions from the soil in order to produce proteins.
1. State five uses of glucose.

2. Explain why glucose is stored as starch.

3. Explain why a seed needs a store of fats/oils for growth.

4. Name the molecules necessary to synthesise proteins.

Prove It!

25
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Aerobic and anaerobic respiration
Ref. Ref.
Key information:
4.4.2.1 - Cellular respiration is an exothermic reaction which is continuously occurring in
living cells.
- Respiration releases the energy needed for living processes.
- Anaerobic respiration in yeast is also known as fermentation.
1. Write a word and balanced symbol equation for aerobic respiration.

2. Compare the processes of aerobic and anaerobic respiration. Give at least

three differences.

3. Outline three uses of the energy released in respiration.

4. Using equations, outline the difference between anaerobic respiration in

muscles and in plants/yeast.

5. State two uses of fermentation.

Prove It!

(3)

26
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Response to exercise
Ref. Ref.
Key information:
4.4.2.2 - During exercise the human body reacts to the increased demand for energy.
- The heart rate, breathing rate and breath volume increase during exercise to
supply the muscles with more oxygenated blood.
- If insufficient oxygen is supplied, anaerobic respiration takes place in muscles.
This causes a build-up of lactic acid which causes muscles to become fatigued
and stop contracting.
(HT ONLY)
- Blood flowing through the muscles transports the lactic acid to the liver where it
is converted back into glucose. Oxygen debt is the amount of extra oxygen the
body needs after exercise to react with the accumulated lactic acid and
remove it from the cells.
1. Explain why the heart rate must increase during exercise.

2. Explain why the breathing rate must increase during exercise. Suggest what
happens to the volume of breath breathed in.

3. Explain what causes cramp and why.

4. Describe what an oxygen debt is.

5. HT ONLY – Describe how lactic acid is converted into glucose.

Prove It!

27
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec. Metabolism
Ref. Ref. (PLEASE NOTE: This section is covered in more detail throughout the course. It is
important however to appreciate how all reactions in the body are linked.)

4.4.2.3 Key information:

- Metabolism is the sum of all reactions in a cell or the body.

1. Name a metabolic reaction that occurs in all cells.

2. Identify the building blocks (monomers) of the following molecules:

- Carbohydrates:
- Lipids:
- Proteins:

3. Explain why glucose is converted to starch in plants, and glycogen in animals.

4. Describe the structure of a lipid.

5. Explain how excess proteins are excreted.

Prove It!

28
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Homeostasis
Ref. Ref.

4.5.1 Key information:

- Homeostasis is the regulation of the conditions inside a cell or organism.

1. What 3 variables are controlled in the body by homeostasis?

2. Why do cells need optimum conditions?

3. Complete the table to explain what each part of the control centre does:
Part of the control system Example What it does
Receptors
Receive and process
information from receptors
Muscles or glands

Prove It!

29
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Structure and function of the human nervous system
Ref. Ref.
Key information:
4.5.2.1 - The nervous system enables humans to react to their surroundings and to
coordinate their behaviour.
- Reflex actions are rapid; they do not involve the conscious part of the brain.
4. What is the function of the central nervous system? Identify its two main parts.

5. Order the following into a reflex arc:

COORDINATOR (CNS) STIMULUS EFFECTOR RESPONSE R ECEPTOR

_____________  _____________  ______________  _____________  ____________

6. Explain why it is important that reflex actions are rapid.

7. Describe how information passes through the nervous system including the
names of the neurones, a description of how the synapses work and what
effectors and receptors are/do.

8. Describe how a sensory neurone is adapted to carry out its function.

Prove It!

(6)

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 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec. Required practical 6 (biology: required practical 7): Plan and carry out an investigation
Ref. Ref. into the effect of a factor on human reaction time.
1. Identify two factors that can affect human reaction time.
4.5.2.1

AT 1, 2. Describe a method for using a ruler to investigate human reaction time.

3, 4

3. Describe how to make sure that the results are reliable.

4. State the receptor and effector in the investigation you have described.

Maths Skills
MS 2c

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 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Human endocrine system
Ref. Ref.
Key information:
4.5.3.1 - The endocrine system is composed of glands which secrete hormones directly
into the bloodstream. The blood carries the hormone to a target organ where it
produces an effect.
- The pituitary gland in the brain is a ‘master gland’ which secretes several
hormones into the blood in response to body conditions. These hormones in turn
act on other glands to stimulate other hormones to be released to bring about
effects
1. Identify the structures associated with the endocrine
system:
K:
L:
M:
N:
O:
P:

2. Describe, using an example, the role of the pituitary

gland.

3. Name the hormone released by:

a) The testes
b) The adrenal gland
c) The thyroid gland

4. Compare the action of the endocrine system with the nervous system.

Prove It!

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 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Contraception
Ref. Ref.
1. Complete the table to explain how each method of controlling fertility works.
4.5.3.5 Contraceptive Method How it works
Oral contraceptives
(the pill)
Injection/Implant/Patch
Barrier method e.g.
condoms/ diaphragms
Intrauterine Devices
e.g. coil
Spermicidal agents

Timed abstinence
Surgical sterilisation e.g.
vasectomy
2. Identify the methods in the table above that are hormonal contraception.

3. Explain why some people oppose the use of contraception.

4. Some people choose to avoid having sexual intercourse when an egg may
be in the oviduct. Evaluate this method of contraception.

Prove It!

33
 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
The use of hormones to treat infertility (HT ONLY)
Ref. Ref.
Key information:
4.5.3.6 - Fertility drugs can be given to women to help them become pregnant
naturally.
- In Vitro Fertilisation (IVF) is an alternative method used by couples unable to
get pregnant.
1. Name the hormones in the drug given to women to help them become
pregnant ‘normally’.

2. Explain how these drugs interact to trigger the release of an egg.

3. Describe the process of IVF.

WS1.3 4. Evaluate (outline the advantages of disadvantages) the use of IVF as a fertility
WS1.4 treatment.

Prove It!

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 Combined Science Trilogy Revision Booklet

Cells and systems

Book Spec.
Negative feedback (HT ONLY)
Ref. Ref.
Key information:
4.5.3.7 - Negative feedback processes ensure internal conditions are maintained within
a narrow range.
1. Name the hormone secreted by the adrenal gland.

2. Describe the effect of this hormone on heart rate. Explain the importance of this.

3. Describe the role of thyroxine in the human body.

4. Explain the concept of negative

feedback, using thyroxine level control as an
example.

Prove It!

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Genetics and Evolution Keywords

Add all the important keywords for this big idea in the grid below
as you come across them in the study pack.

Word Definition

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Genetics and evolution

Boo Spec.
k Ref. Chromosomes
Ref.
4.1.2.1
Key information:
- The nucleus of a cell contains chromosomes made of DNA molecules. Each
chromosome carries a large number of genes. In body cells the chromosomes are
normally found in pairs.

1. Order the following in terms of size (smallest to largest)

CHROMOSOME NUCLEUS GENE CELL

2. Explain why we have two copies of each chromosome.

3. State what is meant by the term ‘gene’.

4. Identify the two types of cell in the human body which contain half a set of
chromosomes. Outline the importance of this.

Prove It!

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 Combined Science Trilogy Revision Booklet

Genetics and evolution

Book Spec.
Mitosis and the cell cycle
Ref. Ref.
4.1.2.2 Key information:
- Cells divide in a series of stages called the cell cycle. During the cell cycle, the
genetic material is doubled and then divided into two genetically identical
daughter cells.
- Mitosis is important in the growth, repair and development of multicellular
organisms.

1. Name the organelle which contains genetic material.

2. Describe what happens in the 3 phases of the cell cycle.

3. Explain why a cell needs to grow before dividing by mitosis.

4. State the number of chromosomes in a human body cell:

a) During stage 1 of the cell cycle:
b) Just before mitosis:
c) Just after mitosis:

5. Suggest why a root tip can be used for observing mitosis under the microscope.

Prove It!

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 Combined Science Trilogy Revision Booklet

Genetics and evolution

Book Spec.
Stem cells
Ref. Ref.
4.1.2.3 Key information:
- A stem cell is an undifferentiated cell of an organism which is capable of giving rise
to many more cells of the same type, and from which certain other cells can arise
from differentiation.
- Stem cells from embryos can be cloned and made to differentiate into most
different types of human cells. Stem cells from adult bone marrow can form many
types of cells including blood cells. Treatment with stem cells may be able to help
conditions such as diabetes and paralysis. Meristem tissue in plants can differentiate
into any type of plant cell, throughout the life of a plant.
WS1.3 1. Define the term ‘stem cell’.

2. Describe the function of stem cells in:

a) Embryos

b) Adult animals

c) Meristems in plants

3. Describe the process of therapeutic cloning using embryos.

4. Evaluate the use of embryonic stem cells for the treatment of diseases such as
diabetes.

5. Stem cells from meristems can be used to produce clones quickly and
economically. Describe two uses of this technique.

Prove It!

(4)

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Genetics and evolution

Boo Spec.
k Ref. Cancer
Ref.
4.2.2.
Key information:
7
- Cancer is the result of changes in cells that lead to uncontrolled growth and
division.
- Tumours can be malignant or benign.
- Both genetic factors and lifestyle choices can affect an individual’s likelihood of
developing cancer.
1. What is cancer?

2. Outline the difference between a benign and a malignant tumour.

3. Describe how malignant tumours spread.

4. Suggest why cancer is more common in older people.

5. Identify three lifestyle choices that can increase an individual’s risk of developing
cancer.

6. Breast cancer is an example of a type of cancer that sometimes runs in families.

Suggest why.

Prove It!

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 Combined Science Trilogy Revision Booklet

Genetics and evolution

Book Spec.
Ref. Ref. DNA and the genome

4.6.1.4 Key information:

- The genetic material in the nucleus is composed of a chemical called DNA. DNA
is a polymer made up of two strands forming a double helix. The DNA is
contained in structures called chromosomes.
- Genes code for a particular sequence of amino acids which make a specific
protein.
- The genome of an organism is the entire genetic material of that organism. The
whole human genome has now been studied and this will have great
importance for medicine in the future.
1. Describe the basic structure of DNA.

2. State the number of chromosomes in a normal human body cell.

3. Define the term ‘gene’. Outline what a gene codes for.

4. Explain the difference between a gene and a genome.

5. Name the project which took twenty years to complete and involved mapping
the entire human genome.

6. Outline the importance of understanding the human genome.

Prove It!

(3)
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Genetics and evolution

Book Spec.
Inherited disorders
Ref. Ref.
4.6.1.7 Key information:
- Some disorders are caused by the inheritance of certain alleles, e.g. cystic
fibrosis and polydactyly.
MS 2d 1. Name a genetic disorder caused by a recessive allele. Describe the symptoms of
this disorder.

2. Explain why disorders caused by dominant alleles are more common than
disorders caused by recessive alleles.

3. HT ONLY: Construct a Punnett Square to show the possible genotypes and

phenotypes of the offspring between two cystic fibrosis carriers. What is the
proportion of healthy offspring to offspring with cystic fibrosis? What is the
probability that their child will have cystic fibrosis?

4. Explain why embryos are screened for genetic disorders. Suggest reasons why
some people are against the screening of embryos for polydactyly, despite it
being caused by a dominant allele.

5. Describe the role of gene therapy in reducing the number of individuals who
suffer from cystic fibrosis.
Prove It!

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Genetics and evolution

Book Spec.
Sex determination
Ref. Ref.
4.6.1.8
Key information:
- Human body cells contain a pair of chromosomes, which carry the genes that
determine sex.

1. State the number of chromosomes found in human body cells.

2. A person has the genotype XX. State whether this person is male or female.

3. State the probability of a couple having a male. Carry out a genetic cross to
support your answer.

Prove It!

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 Combined Science Trilogy Revision Booklet

Genetics and evolution

Book Spec.
Variation
Ref. Ref.
4.6.2.1 Key information:
- There is extensive variation within a population of a species.
- The phenotype (observable characteristics) of an organism is affected by both
genetics and the environment.
- Mutations occur continuously. Very rarely, a mutation will lead to a new
characteristic. If the new characteristic is advantageous it can lead to a change in
the species.
1. Give two examples each of variation caused by:
 genes -
 the environment -
 both -

2. State what causes variation.

3. Explain why there is extensive variation in human skin colour.

4. Describe, using an example, how a mutation can result in a change in a species.

Prove It!

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 Combined Science Trilogy Revision Booklet

Genetics and evolution

Book Spec.
Evolution
Ref. Ref.
4.6.2.2 Key information:
- The theory of evolution states that all species of living things have evolved from
simple life forms that first developed more than three billion years ago.
- Evolution is a change in the inherited characteristics of a population over time
through a process of natural selection, which may result in the formation of a new
species.
- If two populations of one species become so different that they are no longer able
to interbreed to produce fertile offspring, they have formed two new species.
1. State what is meant by the term ‘evolution’.

2. Describe the process of evolution by natural selection.

3. Define the term ‘species’.

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 Combined Science Trilogy Revision Booklet

4. The diagram shows an evolutionary

tree. Identify the species which is:
a) the most closely related to humans.

b) the most distantly related to humans.

Prove It!

Genetics and evolution

Book Spec.
Selective breeding
Ref. Ref.
4.6.2.3 Key information:
- Selective breeding is the process by which humans breed plants and animals for
particular genetic characteristics. Humans have been doing this for thousands of
years since they first bred food crops from wild plants and domesticated animals.
- Selective breeding can lead to ‘inbreeding’, where some breeds are particularly
prone to disease or inherited defects.

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 Combined Science Trilogy Revision Booklet

1. Give three uses of selective breeding.

2. Describe why selective breeding is known as ‘artificial selection’.

3. Describe the process of selective breeding. Explain why it occurs over many
generations.

4. Pedigree dogs are often selectively bred. Outline the advantages and
disadvantages of this.
Prove It!

(4)

Genetics and evolution

Boo Spec
k . Ref. Classification of living organisms
Ref.

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 Combined Science Trilogy Revision Booklet

4.6.4 Key information:

- Traditionally living things have been classified into groups depending on their
structure and characteristics in a system developed by Carl Linnaeus.
- As evidence of internal structures become more developed due to improvements
in microscopes, and the understanding of biochemical processes progressed, new
models of classification were proposed.
- Due to evidence available from chemical analysis there is now a three domain
system developed by Carl Woese.
1. Outline the Linnaeus system of classification.

2. Describe what is meant by the term ‘binomial naming system’.

3. Outline the three domains proposed by Carl Woese.

4. Humans are known as Homo sapiens. State the genus of humans.

5. Explain why classification systems are continually developing.

Prove It!

Interdependence Keywords
Add all the important keywords for this big idea in the grid below
as you come across them in the study pack.
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 Combined Science Trilogy Revision Booklet

Word Definition

Interdependence
Book Spec.
Communities
Ref. Ref.
4.7.1.1 Key information:
- An ecosystem is the interaction of a community of living organisms with the non-
living parts of their environment.

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- Organisms require a supply of materials from their surroundings and other living
organisms there.
- Plants compete with each other for light, space, water and mineral ions.
- Animals compete with each other for food, mates and territory.
- Interdependence means that communities of species depend on other species
for food, shelter, pollination, water etc. If one species is removed, it can affect
the whole community.
- In a stable community, all the species and environmental factors are in balance
and population sizes remain fairly constant.
1. Define the term ‘ecosystem’.

2. Explain why plants must compete for light.

3. Bees are pollinators. Describe the importance of bees to plants within a

community.

4. Give another example of interdependence.

5. What is meant by the term ‘stable community’?

MS 4a Prove It!

(3)

Interdependence
Book Spec.
Biotic and Abiotic factors
Ref. Ref.
4.7.1.2 Key information:
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 Combined Science Trilogy Revision Booklet

- Non-living factors which affect a community are known as abiotic factors.

4.7.1.3 - Examples include: light intensity (photosynthesis), temperature (enzymes),
moisture levels, soil pH and mineral content, wind intensity and direction, carbon
dioxide levels (plants), oxygen levels (aquatic animals).
- Living factors which affect a community are known as biotic factors.
- Examples include: availability of food, new predators arriving, new pathogens,
one species outcompeting another so the numbers are no longer sufficient to
breed.
1. Outline the difference between biotic and abiotic factors, using examples.

2. Give two factors for which animals may compete.

3. State the process that occurs in animals and plants which requires oxygen.
Explain the importance of this process for growth.

4. Give two reasons why plants grow slowly in winter.

MS 4a Prove It!

WS 1.2

Interdependence
Book Spec.
Adaptations
Ref. Ref.
4.7.1.4 Key information:
- Adaptations are features that enable them to survive in the conditions in which
they normally live. These adaptations may be structural, behavioural or functional.
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 Combined Science Trilogy Revision Booklet

- Extremophiles live in environments that are very extreme, such as at high

temperature, pressure, or salt concentration.
1. Describe how a cactus is adapted to survive in the desert.

2. Explain how having a large surface area to volume ratio keeps an organism cool.

3. Describe what is meant by the term ‘extremophile’, using an example.

Prove It!

(6)

Interdependence
Book Spec.
Levels of organisation
Ref. Ref.

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4.7.2.1
Key information:
- Photosynthetic organisms (plants and algae) are the producers of biomass for life
on Earth.
- Transects and quadrats are used to determine the distribution and abundance
of species in an ecosystem.
- All organisms are part of a food chain:
Producer  Primary consumer  Secondary consumer  Tertiary consumer
- Predators kill and eat other animals. Prey are the animals eaten.

1. Name the producer in this food chain. State the process that the producer uses
to produce glucose.
2. Name the tertiary consumer.
3. Describe, using examples from the food chain, the relationship between a
predator and prey.

4. Define the term ‘biomass’.

Prove It!

Interdependence

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 Combined Science Trilogy Revision Booklet

Book Spec. Required practical 7 (biology: required practical 9): Measure the population size of a
Ref. Ref. common species in a habitat. Use sampling techniques to investigate the effect of a
factor on the distribution of this species.
4.7.2.1 Key information:
- Quadrats are used to measure the abundance of plants or slow moving
organisms in an area. The area to be sampled is given grid references and a
AT 1, random number generator is used to randomly place the quadrat in different
3, 4, 6 places. This reduces bias and increases validity.
- Transects can be used to measure how the distribution and abundance of plants
changes across a certain distance.
- Repeats are used in order that a mean number of organisms can be calculated.
This ensures repeatability
- Other scientists may carry out the same investigation. This ensures reproducibility.
WS
2.2

Describe how the student would use the equipment shown to estimate how many
clover plants there are in the school field.

Maths skills
MS 1. Calculate the mean
2b, 2f average of clover plants. Make sure
to remove anomalous results.

2. Calculate the estimated

number of clover plants in the
school field.

3. Identify the mode number of

clover plants from the results in the
table above.

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Interdependence
Book Spec.
How materials are cycled
Ref. Ref.
4.7.2.2 Key information:
- The carbon cycle returns carbon from organisms to the atmosphere as carbon
dioxide to be used by plants in photosynthesis.
- The water cycle provides fresh water for plants and animals on land before
draining into the seas. Water is continuously evaporated and precipitated.
- Microorganisms cycle materials through an ecosystem through the process of
decay. As the microorganisms respire, they release the carbon trapped in
materials as carbon dioxide into the atmosphere. At the same time, mineral ions
are released to the soil.
1. Give an example of a material that is cycled through an ecosystem.

2. Name the process plants carry out which converts carbon dioxide into organic
compounds (glucose). Outline three uses of this glucose in plants.

3. Name the process carried out by animals and plants that releases carbon
dioxide back into the atmosphere.

4. Describe the role of micro-organisms in the cycling of nutrients.

Prove It!

(6)

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 Combined Science Trilogy Revision Booklet

Interdependence
Book Spec.
Biodiversity
Ref. Ref.
4.7.3.1 Key information:
- Biodiversity is the variety of all the different species of organisms on Earth, or
within an ecosystem.
- A great biodiversity ensures the stability of ecosystems by increasing the
availability of food and shelter for organisms.
- Many human activities, such as deforestation, are reducing biodiversity. Only
recently have measures been taken to try and stop this reduction. One way is
carbon sequestration.
WS 1. Define the term ‘biodiversity’.
1.4
2. Suggest why deforestation causes a reduction in biodiversity. Explain the
negative impact of this to human populations.

3. Outline one way in which carbon can be ‘sequestered’. Give a reason why
carbon sequestration is important.

Prove It!

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Interdependence
Book Spec.
Waste management
Ref. Ref.
4.7.3.2 Key information:
- Rapid growth in the human population and an increase in the standard of living
mean that increasingly more resources are used and more waste is produced.
- Pollution kills plants and animals which can reduce biodiversity.
- Water pollution can occur from sewage, fertiliser or toxic chemicals.
- Air pollution can occur from smoke and acidic gases.
- Land pollution can occur from landfill and from toxic chemicals.

1. Describe why pollution can result in a loss of biodiversity.

2. Name two human activities which result in air pollution.

3. Sewage reduces the concentration of oxygen in water. Explain why this results in
a loss of biodiversity.

4. Suggest how we can reduce the amount of land pollution.

5. Explain why waste management is becoming more important.

Prove It!

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Interdependence
Book Spec.
Land use
Ref. Ref.
4.7.3.3 Key information:
- Humans reduce the amount of land available for other animals and plants by
building, quarrying, farming and dumping waste.
- Peat bogs are wetland areas made up of partially decomposing material. Peat is
used as garden compost because it contains a high concentration of mineral
ions. The destruction of peat bogs results in a loss of biodiversity.
- The decay or burning of peat releases carbon dioxide into the environment.
WS 1. Identify four ways in which humans reduce the amount of land available for
1.4, other animals and plants.
1.5
2. Explain why farmers often use peat as a fertiliser.

3. Describe why the burning of peat contributes to global warming.

4. Evaluate (consider the reasons for and against) the use of peat as a fertiliser for
growing crops.

Maths skills
WS
3.5

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Interdependence
Book Spec.
Deforestation
Ref. Ref.
4.7.3.4
Key information:
- Large-scale deforestation in tropical areas has occurred in order to provide land
for cattle and rice fields, and grow crops for biofuel.

WS 1. Describe why deforestation has occurred in tropical areas.

1.4

2. Evaluate (consider the reasons for and against) the carrying out of large-scale
deforestation in order to provide land for cattle and rice fields.

3. Explain, using your knowledge of the carbon cycle, why deforestation affects
the composition of atmospheric gases.

Prove It!

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Interdependence
Book Spec.
Global warming
Ref. Ref.
4.7.3.5 Key information:
- Global warming is the observed increase in the average surface temperature
due to the effect of greenhouse gases. Increasing levels of the two main
greenhouse gases, carbon dioxide and methane, are contributing to global
WS warming.
1.6 - Scientific publications are always peer-reviewed. Scientists review each other’s
work regularly in order to understand more about global warming and climate
change. During this process, scientists try and repeat each other’s work in order
to check its validity and give each other feedback.
1. Describe, using examples, the consequences of global warming for biodiversity.

2. Give three reasons why the levels of carbon dioxide and methane in the
atmosphere are increasing.

3. Describe the process of peer-review. Explain why it is important.

Prove It!
WS
1.4

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Interdependence
Book Spec.
Maintaining biodiversity
Ref. Ref.
4.7.3.6 Key information:
- Scientists and concerned citizens have put in place programmes to reduce the
negative effects of humans on ecosystems and biodiversity. These include
breeding programmes for endangered species, protection and regeneration of
rare habitats, re-introduction of hedgerows in agricultural areas where farmers
grow only one type of crop, reduction of deforestation and carbon dioxide
emissions and recycling initiatives.
1) Explain why breeding programmes are important for maintaining biodiversity.

2) Suggest why rare habitats are protected. Describe the effect of this on global
biodiversity.

3) Explain why hedgerows between fields are important for maintaining biodiversity.

4) Give three examples of materials which can be recycled. Outline two environmental
benefits of recycling.

Prove It!
WS
1.4

(4)

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Microbes and Health Keywords

Add all the important keywords for this big idea in the grid below
as you come across them in the study pack.

Word Definition

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Microbes and Health

Book Spec.
The human digestive system
Ref. Ref.
4.2.2.1
Key information:
- The digestive system is an organ system where several organs work together to
absorb and digest food.
- Digestive enzymes convert large insoluble molecules into smaller soluble ones so
they can be absorbed into the blood stream.

1. Complete the table to summarise the role of the organs in the digestive system:
Organ Role
Salivary glands
Oesophagus
Stomach
Liver
Pancreas
Small intestine
Large intestine
2. What does a digestive enzyme do?

3. Complete the table about enzymes:

Large insoluble
Small soluble Where the Where the
molecule the
Enzyme molecule(s) that enzyme is enzyme
enzyme breaks
are formed produced works
down
Carbohydrase

Fats (lipids)

Amino acids
4. Explain enzyme action using the lock and key theory.

5. Describe the 2 functions of bile and state where it is made and where it is stored.

Prove It!

A student has eaten a steak for dinner. The steak contains protein and fat.

(i) Describe how the protein is digested.

(3)

(ii) Explain two ways in which bile helps the body to digest fat.

(4)

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Microbes and Health

Book Spec. Required practical 3 (biology: required practical 4): Use qualitative reagents to test for
Ref. Ref. a range of carbohydrates, lipids and proteins.
4.2.2.1 1. Outline how you would prepare a sample of solid food for a food test.

AT2,8
2. Complete the table to summarise the 4 food tests:
What type What does the
Test does it test What is the method? positive result look
for? like?

Benedict’s

Iodine
solution

Biuret

Sudan III

Risk Assessment
WS2.4 Outline any hazards in this experiment along with the associated risks and how to
minimise them.

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Microbes and Health

Book Spec. Required practical 4 (biology: required practical 5): Investigate the effect of pH on
Ref. Ref. the rate of reaction of amylase enzyme.
4.2.2.1 1. Outline a method for this practical that uses a continuous sampling
technique.
AT1,2,5,8

WS2.1
WS2.2
WS2.5

2. Suggest a hypothesis for the experiment outlined above.

3. Identify 3 possible sources of error in the experiment and identify how you
would control or monitor them.

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Microbes and Health

Book Spec.
Coronary heart disease: a non-communicable disease
Ref. Ref.
1. Describe what has happened inside the body of someone who has coronary
4.2.2.4 heart disease.

2. Describe the consequence of a person having a faulty valve and the methods
used to treat it.

3. Complete the table to summarise some treatments for CHD:

Treatment Description of treatment When it is used

Statins

Stents

Mechanical
or
biological
valves

Transplant

Prove It!

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 Combined Science Trilogy Revision Booklet

Microbes and Health

Book Spec.
Health Issues and the effect of lifestyle on some non-communicable diseases
Ref. Ref.
1. State 3 lifestyle factors that can affect both mental and physical health.
4.2.2.5
4.2.2.6
2. Which type of pathogen, living in cells, can be a trigger for cancer?

3. What can immune reactions (originally caused by a pathogen) be a trigger

for?

4. What mental illness can severe physical health problems cause?

5. What physical problems can smoking cause?

6. Which organs does drinking alcohol affect the most?

Maths Skills
MS2c
MS4a

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Microbes and Health

Book Spec.
Cancer
Ref. Ref.
1. Describe what is happening to cells in someone with cancer.
4.2.2.7

2. What is a benign tumour?

3. How are malignant tumours different to benign tumours?

4. Suggest three factors that are linked with an increased risk of getting cancer.

Prove It!

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 Combined Science Trilogy Revision Booklet

Microbes and Health

Book Spec.
Communicable Diseases
Ref. Ref.
4.3.1.1 Key information:
- Pathogens are microorganisms that can cause disease. They can infect plants or
animals and can be spread by direct contact, water or air.

1. Define the term ‘pathogen’.

2. State the names of the 4 types of pathogen.

3. Suggest 2 ways the spread of disease can be reduced or prevented.

4. How do bacteria make you feel ill?

5. How do viruses make you feel ill?

Prove it!
1. a) What causes infectious diseases? (1)

……………………………………………………………………………………………………………….

a) How do pathogens make you feel ill? (2)

………………………………………………………………………………………………………………

2. a) Give two ways in which diseases are spread from one person to another. (2)

………………………………………………………………………………………………………………

………………………………………………………………………………………………………………

b) Give two ways in which diseases are spread from one plant to another. (2)
………………………………………………………………………………………………………………

………………………………………………………………………………………………………………

c) For each method given in part a) and part b), explain how the pathogens are
passed from one organism to another. (4)

………………………………………………………………………………………………………………

………………………………………………………………………………………………………………

………………………………………………………………………………………………………………

………………………………………………………………………………………………………………

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Microbes and Health

Book Spec.
Viral and Bacterial Diseases
Ref. Ref.
4.3.1.2 Key information:
4.3.1.3 - The flu (influenza), measles, HIV and tobacco mosaic virus (TMV) are all
examples of viral diseases.
- Salmonella which causes food poisoning and Gonorrhoea (a sexually
transmitted infection) are caused by bacteria.
1. Complete the table about viral diseases.

Affects
How can it be
humans
Disease Symptoms How is it spread? prevented or
or
treated?
plants?
Measles

HIV

TMV N/A N/A

2. Complete the table about bacterial diseases.

How can it be prevented

Disease Symptoms How is it spread?
or treated?
Salmonella

Gonorrhoea

Prove It!

(3)

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 Combined Science Trilogy Revision Booklet

Microbes and Health

Book Spec.
Fungal and Protist Diseases
Ref. Ref.
4.3.1.4 Key information:
4.3.1.5 - Rose black spot is a fungal disease affecting plant growth.
- Malaria is caused by protists.

1. Complete the table about fungal and protist diseases.

Affects Caused
How can it be
humans by protist How is it
Disease Symptoms prevented or
or or spread?
treated?
plants? fungus?
Rose
black
spot

Malaria

Prove It!

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 Combined Science Trilogy Revision Booklet

Microbes and Health

Book Spec.
Human Defence Systems
Ref. Ref.
4.3.1.6 1. Complete the table to summarise the defence systems of the human body:
Body Part How it defends against pathogens
Skin

Nose

Trachea
and bronchi
Stomach

2. Describe the 3 ways which white blood cells defend the body against
pathogens.

Prove It!

(3)

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 Combined Science Trilogy Revision Booklet

Microbes and Health

Book Spec.
Vaccination
Ref. Ref.
Key information:
4.3.1.7 - Spread of pathogens can be reduced by vaccinating a large amount of the
population.
- A vaccine prevents an individual becoming infected with and spreading a
specific pathogen.
- Vaccinations work by introducing small amounts of dead/inactive pathogens
into the body causing the white blood cells to respond.
1. What does a vaccination contain?

2. Describe how a vaccination protects a person from becoming infected by a

specific pathogen.

3. Evaluate the idea that it should be compulsory for all parents to get their child
vaccinated.

Prove It!

1. Describe other differences in antibody production after infection compared

with after vaccination. (3)

2. Vaccination against measles will not protect a child against rubella. Why? (1)

3. What is the advantage of protecting a large proportion of the population

against measles? (1)

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Microbes and Health

Book Spec.
Antibiotics and Painkillers
Ref. Ref.
1. What is an antibiotic? Give an example.
4.3.1.8

2. Why are doctors being encouraged to reduce the amount of antibiotics they
are prescribing?

3. Why can antibiotics not be used to treat the flu?

4. Why is it difficult to create a drug that kills the flu?

5. What is a painkiller? How is it different to an antibiotic?

Prove It!

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 Combined Science Trilogy Revision Booklet

Microbes and Health

Book Spec.
Detection and identification of plant diseases (biology only - HT only)
Ref. Ref.
HT 1. List 7 ways plant diseases can be detected.
and
triple
only
4.3.3.1
2. List 3 ways an identification of a plant disease can be made.

3. Other than pathogens, how else can plants get infected? Give an example.

4. Complete the table to summarise the problems plants have with mineral
deficiency:
Ion that is
Problem caused Process interfered with
deficient
Nitrate

Magnesium

Prove It!

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Microbes and Health

Book Spec.
Plant defence responses
Ref. Ref.
1. Describe in detail 3 physical defence responses that plants have to resist
4.3.3.2 invasion of microorganisms.

2. Describe 2 chemical plant defence responses.

3. Suggest 3 mechanical adaptations plants may have to defend against being

eaten by animals.

Prove It!

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Graph drawing

Top tips for getting full marks in graph-drawing questions:

1. Axes should be drawn in pencil.

2. Labels (including units!) should only be written in pen when you are sure
of them.

3. Your scale should be even – 0.1, 0.2, 0.3… or 10, 20, 30… or 100, 200, 300
.... not 18, 22,13.

4. When you draw a bar chart the bars should be of equal width.

5. If you draw a line graph then a line or curve of best fit should show the
pattern of the points – they should not be connected dot to dot.

6. Your graph needs to take up over half of your graph paper. If it doesn’t
then you should redo your scale.

Important terms

Independent variable: this is the variable you have chosen to change.

These are always drawn on the x-axis.

Dependent variable: this changes when you have changed the

independent variable. It depends on the independent variable. These are
always drawn on the y-axis.

Categoric variable: this is the names of groups such as eye colour or type of
energy resource. You draw a bar chart to represent this type of variable.

Continuous variable: this is data such as temperature or time which can be

any value. You draw a line graph to represent this type of variable.

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Graph drawing practice

1. Bar chart

A student carried out a survey to find out the blood group of each student in Year 11. He
calculated the % of students in each blood group, as shown in the table below.

Blood group % students

A 41
B 9
AB 4
O 46

Plot a bar graph of the data shown above.

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Prove it!

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2. Line graph

A student investigated the effect of temperature on the rate of photosynthesis.

Her results are shown in the table below.

Draw a line graph of the data shown above.

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Prove it!

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3. Pie chart
The table below shows the world energy demand and sources of energy in 2013.

Energy source % Calculation Degrees of a

circle (º)
Coal 31 (31/100) x 360 112
Gas 24
Oil 31
Nuclear 4
Hydroelectricity 7
Other renewables 3

Draw a pie chart of the data shown above.

Help! How do I work out the size of each part of the pie chart?

 To draw a pie chart, we need to represent each part of the data as a proportion
of 360, because there are 360 degrees in a circle.
 For example, if 31% of world energy demand comes from coal, we will represent
this on the circle as a segment with an angle of: (31/100) x 360 = 111.6, or 112º.
 Complete the additional columns of the table shown in red above.
 Once you have done this, check that all the values you have calculated add up
to 360º!

Now draw your pie chart!

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Prove it!

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Reflections Page
Each time you come across something you find hard, write it down here
and ask your teacher to help you with it.
Tick when you
Topic I Found Page have got help
What was difficult about this?
Hard Number from your
teacher

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