B2, Chapter 1
Answers
1
Marks
a i D
ii C
iii A
b B and D
c Group of cells – with similar function.
3
2
Nucleus – controls cell activities.
Mitochondria – release energy.
Chloroplasts – absorb light for photosynthesis.
Ribosomes – produce protein.
4
3
a Named plant tissue, e.g. epidermal/mesophyll/xylem/phloem.
Function correctly linked to chosen tissue, covers surface/photosynthesis/
transport.
b i Correctly named animal tissue, e.g. muscular/glandular/epithelial.
(Allow other relevant answer).
ii Correct organ named, which contains named tissue, e.g. stomach.
iii Correct function for named tissue, e.g. contracts to cause
movement/produces enzymes/lines organ.
2
a (Cell) membrane.
b i diffusion
ii Molecules move from a region of higher concentration to a region of
lower concentration.
1
1
a A  nucleus, B  cell wall.
b Mitochondria – release energy/respiration.
Ribosomes – produce protein.
c Solution/liquid/(cell) sap or description e.g. water and sugar.
2
2
4
5
2
2
1
1
1
2
1
6
Marks awarded for this answer will be determined by the standard of the
scientific response as well as the Quality of Written Communication (QWC).
There are no discrete marks for the assessment of written communication but
QWC will be one of the criteria used to assign the answer to an appropriate
level.
There is a clear and detailed description referring to most of the key organs in
the digestive system and their functions, including 5–6 points from the
examples below. The answer shows almost faultless spelling, punctuation
and grammar. It is coherent and in an organised, logical sequence. It
contains a range of appropriate or relevant specialist terms used accurately.
There is a description of at least three organs and their functions with 3–4
points from the examples below. There are some errors in spelling,
punctuation and grammar. The answer has some structure and organisation.
The use of specialist terms has been attempted, but not always accurately.
There is a brief description of the functions of at least two organs, which has
little clarity and detail, with 1–2 points from the examples below. The
spelling, punctuation and grammar are very weak. The answer is poorly
New AQA GCSE Science © Nelson Thornes Ltd 2011
5-6
3-4
1-2
1
B2, Chapter 1
Answers
organised with almost no specialist terms and/or their use demonstrating a
general lack of understanding of their meaning.
No relevant content. (0 marks)
Examples of biology points made in response:
• Glands produce digestive juices
• Salivary glands
• Pancreas
• Digestion occurs in the stomach and small intestine
• The liver produces bile
• The soluble food is absorbed in the small intestine
• Water is absorbed from the undigested food
• In the large intestine.
New AQA GCSE Science © Nelson Thornes Ltd 2011
Marks
0
2
B2, Chapter 2
Answers
1
a i hypothesis
ii line
iii size of quadrat
b i 3.6
ii 3
c Any sensible suggestion relating to method of counting or uncontrolled
variables, e.g. difficulty of counting inside the hedge/quadrat would miss
all snails in top 0.5 metres/hard to see snails under leaves/not all parts of
the hedge are shaded on the shaded side of the field/birds might live in
the hedges not just the trees/allow – snails might move about and be
counted twice.
2
a
There is a clear and detailed description referring to the data in the graph
about light, temperature and carbon dioxide and how to set up a controlled
experiment including 5–6 points from the examples below. The answer
shows almost faultless spelling, punctuation and grammar. It is coherent
and in an organised, logical sequence. It contains a range of appropriate
or relevant specialist terms used accurately.
There is a description of setting up a controlled experiment, including at
least two variables with 3–4 points from the examples below. There are
some errors in spelling, punctuation and grammar. The answer has some
structure and organisation. The use of specialist terms has been
attempted, but not always accurately.
There is reference to setting up several tunnels and mention of at least
one variable, but little clarity and detail, with 1–2 points from the
examples below. The spelling, punctuation and grammar are very weak.
The answer is poorly organised with almost no specialist terms and/or
their use demonstrating a general lack of understanding of their meaning.
No relevant content. (0 marks)
Examples of biology points made in response:
• Use of term ‘limiting factors’
• The more photosynthesis the more growth
• Carbon dioxide optimum around 4%
• Plants need water
• Control of light intensity
• Types of light
• Temperature control/25°C
• Idea that light changes with type of plastic/colour of plastic/thickness of
plastic
• Idea that might need heating/ventilation to control/monitor temperature
• Idea that need to contain the carbon dioxide/have a source of carbon
dioxide gas.
• Reference to having different sets of conditions in each model tunnel to
be able to determine optimum/idea that try slightly lower/higher
New AQA GCSE Science © Nelson Thornes Ltd 2011
Marks
1
1
1
1
1
1
5-6
4-3
1-2
0
1
B2, Chapter 2
Answers
temperature/carbon dioxide level to check cost effectiveness.
b Any one from the following:
• Possible to mimic large scale events/idea of/on a small scale.
• Can be used to predict changes/changes in variables.
•
Allow a description e.g. predict the spread of disease/can predict the
effect of a chemical on all bacteria using a safe organism/can use fast
breeding organisms to mimic processes which occur slowly in
others/can predict the effect of global warming on organisms in a
locality.
New AQA GCSE Science © Nelson Thornes Ltd 2011
Marks
1
2
B2, Chapter 3
Answers
Marks
1
a i catalysts
ii protein
iii amylase
iv bile
v fats
b i It is denatured/changes shape/does not work as well.
ii Temperature (allow concentration).
c Large molecules (of starch) are broken down/changed into small
molecules of sugar.
1
1
1
1
1
1
1
2
2
a Microorganisms.
b i proteases.
ii amino acids (both words).
c i 14 minutes
ii mark independently
enzyme Z.
It takes the least time (to pre-digest protein)/works fastest.
Allow only 7 minutes/less time/faster
(do not allow works best).
iii temperature
pH
1
1
3
There is a clear, balanced and detailed description of the roles of both the
liver and pancreas. The answer shows almost faultless spelling,
punctuation and grammar. It is coherent and in an organised, logical
sequence. It contains a range of appropriate or relevant specialist terms
used accurately.
There is some description of the roles of both the liver and pancreas which
lacks some details. There are some errors in spelling, punctuation and
grammar. The answer has some structure and organisation. The use of
specialist terms has been attempted, but not always accurately.
There is a brief description reference to the role of either the liver or
pancreas. The spelling, punctuation and grammar are very weak. The
answer is poorly organised with almost no specialist terms and/or their use
demonstrating a general lack of understanding of their meaning.
No relevant content.
Examples of biology points made in response:
• liver produces bile
• bile neutralises acid
• acid produced by stomach
• pancreas produces lipase
• lipase is an enzyme
• lipase works best in neutral/alkaline conditions
• lipase catalyses the breakdown of fat to fatty acids and glycerol
New AQA GCSE Science © Nelson Thornes Ltd 2011
1
2
2
5-6
3-4
1-2
0
1
B2, Chapter 3
Answers
Marks
• allow reference to or a description of emulsification.
New AQA GCSE Science © Nelson Thornes Ltd 2011
2
B2, Chapter 4
Answers
1
Marks
a A= nucleus
B = (cell) membrane
C = cytoplasm
b any two from
• (contain) mitochondria
• many (mitochondria)
• respiration (occurs in mitochondria)
3
2
a
b
c
d
1
1
2
2
3
a glucose, carbon dioxide
b i oxygen
ii lactic acid
iii less energy released/needed for muscle contraction/movement
2
1
1
1
4
a 3600
2
2
mitochondria
glucose
carbon dioxide and water (either order)
energy released, used for movement
(If answer incorrect allocate 1 mark for working 18 000 
18 000
 80 )
100
b 21 600
c respiration uses oxygen/is aerobic glucose/sugar is broken down in the
mitochondria to release energy for muscle contraction.
5
There is a clear, balanced and detailed explanation about the
differences between the two races in terms of aerobic and anaerobic
respiration. The answer shows almost faultless spelling, punctuation and
grammar. It is coherent and in an organised, logical sequence. It
contains a range of appropriate or relevant specialist terms used
accurately.
There is some attempt to explain the differences between
the two races in terms of respiration. There are some errors in spelling,
punctuation and grammar. The answer has some structure and
organisation. The use of specialist terms has been attempted, but not
always accurately.
There is a brief description of the differences between the two
races. The spelling, punctuation and grammar are very weak. The
answer is poorly organised with almost no specialist terms and/or their
use demonstrating a general lack of understanding of their meaning.
1
4
5-6
3-4
1-2
0
No relevant content.
Examples of biology points made in response:
• energy transferred faster in 100 m race
• carbon dioxide produced faster during 1500 m race/more
• carbon dioxide produced
• correct reference to twice/half as fast in either/both cases
• respiration during 100 m race (mainly) anaerobic
New AQA GCSE Science © Nelson Thornes Ltd 2011
1
B2, Chapter 4
Answers
•
•
•
Marks
respiration during 1500 m race (mainly) aerobic
aerobic respiration produced carbon dioxide
anaerobic respiration produced lactic acid.
New AQA GCSE Science © Nelson Thornes Ltd 2011
2
B2, Chapter 5
Answers
Marks
1
46
genes characteristics
5
2
a i sexual/sex
ii egg/gamete/sex cell/ovum (reject ovule)
(for 1 mark each)
b i meiosis/reduction
ii mitosis/somatic
c twice as many (reject answers based on 23/46 chromosomes)
for one mark
d i information/genes/DNA passed from parents (chromosomes neutral)
for one mark
ii genes/genetic information/ chromosomes from two parents
alleles may be different
environmental effect/named
may have been mutation
any two for 1 mark each
1
1
a The cells change into other types of cell.
b stem cells
c bone marrow cells
allow other types of adult stem cells – not umbilical cord cells
d It may lead to death of an embryo/An embryo cannot give consent.
allow other ethical reason – not religious reasons
1
1
1
3
4
nucleus
Y
There is a clear, balanced and detailed explanation about the differences
between adult and embryonic stem cells and the uses and advantages of
the adult stem cells. The answer shows almost faultless spelling,
punctuation and grammar. It is coherent and in an organised, logical
sequence. It contains a range of appropriate or relevant specialist terms
used accurately.
There is some attempt to explain the differences between adult and
embryonic stem cells and the benefi ts of adult stem cells. There are some
errors in spelling, punctuation and grammar. The answer has some
structure and organisation. The use of specialist terms has been
attempted, but not always accurately.
There is a brief description of what stem cells do and some evidence of the
uses of stem cells. The spelling, punctuation and grammar are very weak.
The answer is poorly organised with almost no specialist terms and/or their
use demonstrating a general lack of understanding of their meaning.
No relevant content.
1
1
1
1
2
1
5-6
3-4
1-2
0
Examples of biology points made in response:
• Stem cells are able to change into other types of cell
• Stem cells can be removed from adults, e.g. bone marrow
• Embryonic stem cells are taken from early embryos before the cells have
started to change into other cells
• This is unethical because the embryo is destroyed
• There is a risk of cancer with embryonic stem cells
New AQA GCSE Science © Nelson Thornes Ltd 2011
1
B2, Chapter 5
Answers
Marks
• Adult stem cells have been used safely for 40 years
• To treat leukaemia/other named example
• Patients with nervous system disorders have shown improvements after
treatment with adult stem cells
• Accept another relevant point which answers the doctor’s statement
New AQA GCSE Science © Nelson Thornes Ltd 2011
2
B2, Chapter 6
Answers
amphibia reptile birds mammals
cartilage fish
from fossils
diseases
predators
Marks
1
a
b
c
d
2
a All members of a species die out.
b i 900 million (must have the units)
ii 11
iii As the human population rises the number of extinctions rises.
c i 4 [if answer incorrect then 68-64 (1 mark)]
ii E.g. at the beginning of the century people using more land for housing
etc.
Loss of habitat
Industrialisation
Pollution
E.g. at the end of the century more protected species (idea of)
conservation of habitats/reintroduction.
2
1
1
2
2
2
3
a i 600
ii 135–150 millions of years
b i 1/5 or 100/500 or 20%
correct working shown but arithmetic error gains 1 mark
ii any two from:
• environmental change
• new competitor
• new disease
• environmental conditions
• new predator or changing.
1
1
2
2
4
There is a clear, balanced and detailed explanation of speciation starting with
isolation and ending with the inability to interbreed. The answer shows almost
faultless spelling, punctuation and grammar. It is coherent and in an
organised, logical sequence. It contains a range of appropriate or
relevant specialist terms used accurately.
There is some attempt to explain speciation which shows an understanding
of isolation. There are some errors in spelling, punctuation and grammar. The
answer has some structure and organisation. The use of specialist terms has
been attempted, but not always accurately.
There is a brief description of speciation. The spelling, punctuation and
grammar are very weak. The answer is poorly organised with almost no
specialist terms and/or their use demonstrating a general lack understanding
of their meaning.
No relevant content.
Examples of biology points made in response:
• two populations of a species may become separated/idea of geographical
separation
• populations have a wide range of alleles (allow genes)
New AQA GCSE Science © Nelson Thornes Ltd 2011
1
1
1
2
5-6
3-4
1-2
0
1
B2, Chapter 6
Answers
•
•
•
•
•
•
Marks
this leads to variation (of characteristics) in the population
some characteristics may be beneficial
organisms survive to breed
if the populations stay separate/idea that separation maybe for a long time
they become too different
can no longer interbreed.
New AQA GCSE Science © Nelson Thornes Ltd 2011
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