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Title: Edexcel a level biology question paper 3 june 2024 salters Nuffield + mark scheme
Description: Mark Scheme (Results) Summer 2024 Pearson Edexcel A Level GCE In Biology A Salters Nuffield (9BN0) Paper 03: General and Practical Applications in Biology
Description: Mark Scheme (Results) Summer 2024 Pearson Edexcel A Level GCE In Biology A Salters Nuffield (9BN0) Paper 03: General and Practical Applications in Biology
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Edexcel a level biology
question paper 3 june
2024 salters Nuffield +
mark scheme
Please check the examination details below before entering your candidate information
Candidate surname
Centre Number
Other names
Candidate Number
Pearson Edexcel Level 3 GCE
Wednesday 19 June 2024
Morning (Time: 2 hours)
Paper
reference
9BN0/03
Biology A (Salters Nuffield)
Advanced
PAPER 3: General and Practical Applications in Biology
You must have: Ruler, HB pencil, scientific calculator and a copy
of the scientific article adapted from the New Scientist and the
Brazilian Journal of Medical and Biological Research (enclosed)
Total Marks
Instructions
Use black ink or ball-point pen
...
all questions
...
• Show
the questions in the spaces provided
• Answer
– there may be more space than you need
...
• The
marks for each question are shown in brackets
• The
– use this as a guide as to how much time to spend on each question
...
Advice
each question carefully before you start to answer it
...
• Try
• Check your answers if you have time at the end
...
F:1/1/1/1/1/1/1/1/1/1/
*P74458RA0136*
Turn over
1 One of the first plant species to colonise some habitats is thale cress
(Arabidopsis thaliana)
...
(Source: Nigel Cattlin / Alamy Stock Photo)
(a) State what is meant by the term colonisation of a habitat
...
...
2
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Write your answers in the spaces provided
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(b) One role of IAA is to stimulate the phototropic response of shoots
...
(3)
...
...
...
...
...
The diagram shows the roots of thale cress
...
The plants were treated with different concentrations of IAA
...
The graph shows the results of this investigation
...
6
Thale cress
homozygous for:
1
...
2
Mean number of
1
...
8
mutant
tir1 gene
0
...
4
0
...
0
0
...
01
0
...
00
–3
IAA concentration / μmol dm
(i) Explain why the scientists used plants homozygous for the normal and the
mutant tir1 gene in this investigation
...
...
...
...
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One type of receptor for IAA is coded for by the tir1 gene
...
00 µmol dm–3 of IAA
...
%
(iii) Deduce the effect of the mutation in the tir1 gene on the response of
thale cress to IAA
...
...
...
...
...
...
The antibacterial properties of licochalcone A have been investigated
...
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Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterial pathogen that is
resistant to many antibiotics
...
(2)
Mass of
licochalcone A
/ μg
Diameter of
clear zone
/ mm
Area of
clear zone
/ mm2
10
14
...
5
214
40
16
...
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(b) The bacteria used in this investigation are pathogenic
...
(3)
...
...
...
...
...
(c) Explain how an anomalous result could be identified for this investigation
...
...
...
...
The graph shows the effect of three different herbicides, A, B and C, on inhibition
of the Hill reaction in isolated chloroplasts
...
(1)
...
...
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(ii) Calculate the gradient of the slope for herbicide A at 50% inhibition of the
Hill reaction
...
(2)
Answer
...
(2)
...
...
...
...
*P74458RA0936*
9
Turn over
(b) Describe the role of RUBISCO in the light-independent reactions
of photosynthesis
...
...
...
...
...
...
(Total for Question 3 = 8 marks)
10
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(3)
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BLANK PAGE
Turn over
*P74458RA01136*
11
Great white shark
(Source: Mircea Costina / Alamy Stock Photo)
Humpback whale
A typical adult great white shark has a mass of approximately 600 kg
...
The diagram shows the trophic levels for two marine communities, one that includes
the great white shark and one that includes the humpback whale
...
g
...
g
...
g
...
g
...
g
...
g
...
g
...
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(a) Explain why an area of ocean can support a greater biomass of humpback whales
than of great white sharks
...
...
...
...
...
*P74458RA01336*
13
Turn over
(b) Phytoplankton are photosynthetic unicellular microorganisms
...
(1)
...
...
Explain how an oxygen probe could be used to estimate the effect of
temperature on the gross primary productivity (GPP) of phytoplankton
...
...
...
...
...
...
...
...
14
*P74458RA01436*
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Phytoplankton are primary producers in aquatic ecosystems
...
In an experiment, the production of carbon dioxide and the uptake of oxygen by
copepods was measured at 14 °C and at 17 °C
...
1
...
4
1
...
0
0
...
6
0
...
2
0
...
00
0
...
00
1
...
00
–1
(i) Determine the mean ratio of carbon dioxide produced to oxygen consumed
at 17 °C
...
(ii) Deduce two conclusions from the results of this experiment
...
...
...
...
gp120
proteins of host cell
lipid membrane
capsid
protease
viral RNA genome
reverse
transcriptase
(i) State the role of gp120 in the life cycle of the HIV virus
...
...
(ii) Give a reason why there are proteins from the host cell in the lipid membrane
surrounding the virus particle
...
...
16
*P74458RA01636*
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5 Human immune deficiency virus (HIV) can cause acquired immune deficiency
syndrome (AIDS)
...
A polyprotein is a chain of smaller proteins
...
The diagram shows the individual proteins produced from the polyprotein by
HIV protease
...
p6
(3)
...
...
...
...
...
The graph shows the effect of polyprotein concentration on the initial rate of
reaction of normal HIV protease and inhibitor‑resistant HIV protease
...
(2)
Answer
...
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(ii) Explain the importance of enzyme and substrate concentrations when
comparing the initial rates of reaction of different enzymes
...
...
...
...
...
(Total for Question 5 = 10 marks)
*P74458RA01936*
19
Turn over
(a) This damage can cause changes in behaviour
...
(i) Explain how MDMA changes the rate of transmission of nerve impulses across
serotonin synapses
...
...
...
...
...
...
...
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(ii) The effect of MDMA on the behaviour of mice has been investigated
...
When they pressed the MDMA button they received a dose of MDMA
...
The buttons were activated for one three-hour period each day
...
25
20
Number of
button presses
in 3 hours
MDMA button
15
10
5
Control button
0
1
2
3
4
6
5
7
8
9
10
Day
Determine the effect of MDMA on the number of button presses made by
these mice
...
...
...
...
...
Retention of
water in the
body
Fall in blood
solute
concentration
Swelling of the
brain cells
Constriction of
blood vessels in
the brain
Death
Brain cells regulate their volume using active transport of sodium ions
...
(2)
...
...
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(ii) Explain how the active transport of sodium ions can regulate brain
cell volume
...
...
...
...
...
(iii) Explain why swelling of the brain cells will result in vasoconstriction
...
...
...
...
...
...
(Total for Question 6 = 16 marks)
24
*P74458RA02436*
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* 7 Sports injuries can be treated to reduce pain caused by muscle cramp
...
The compound action potential (CAP) is a measure of the sum of all action potentials
in a muscle
...
The diagram shows the latency, duration and amplitude for a CAP
...
*P74458RA02536*
25
Turn over
The effects of the different treatments on the CAP for motor and sensory neurones
are shown in the graphs
...
Use all the information provided in the question as well as your own knowledge
and understanding
...
...
...
...
...
...
...
...
...
...
...
...
...
...
...
...
(Total for Question 7 = 9 marks)
*P74458RA02736*
27
Turn over
Use the information from the scientific articles and your own knowledge to answer
the following questions
...
(3)
...
...
...
...
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(b) Describe how the algae living on the hair of sloths can be shown to belong to one
of four phyla (Box 2)
...
...
...
...
...
...
...
...
...
...
...
...
...
(d) Explain how the presence of different antibodies can be used to show that some
viruses are specific to sloths and some are incidental (Box 3)
...
...
...
...
...
30
*P74458RA03036*
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(4)
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(e) Sloths have ‘the longest digestive process on record for a plant-eating mammal’
(paragraph 7)
...
(2)
...
...
...
(f ) Explain why ‘maintaining a core body temperature is energetically expensive’ for a
sloth (paragraphs 8 and 9)
...
...
...
...
...
(g) Sloths can warm up by climbing higher up into the canopy (paragraph 9)
...
(1)
...
(3)
...
...
...
...
...
Deduce how the enzymes in sloth muscles will differ from those in
human muscles
...
...
...
...
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(j) Sloths carry a ‘community of commensal beetles, mites and moths’
...
(2)
...
...
...
...
...
(3)
...
...
...
...
...
(Total for Question 8 = 30 marks)
TOTAL FOR PAPER = 100 MARKS
*P74458RA03336*
33
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*P74458RA03536*
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Pearson Edexcel Level 3 GCE
Wednesday 19 June 2024
Morning (Time: 2 hours)
Paper
reference
9BN0/03
Biology A (Salters Nuffield)
Advanced
PAPER 3: General and Practical Applications in Biology
Scientific article for use with Question 8
Do not return the insert with the question paper
...
F:1/1/1/1/1/1/1/1/1/1/
*P74458RA*
LIFE IN THE SLOTH LANE
Once defamed as slow and stupid, sloths are now recognised as masterworks of mammalian
evolution – and we could all learn from their energy‑saving tricks
...
Jonathan Ross ISTOCK PHOTO
1
...
He proclaimed the
Americas “degenerate”, a sodden, miserable land filled with weak and inferior species
...
2
...
and even
habitual sadness”
...
One more defect would have made their existence impossible
...
Buffon couldn’t have been more wrong
...
In fact, the closer we look at sloth biology, the more we see just how hard
evolution has had to work so that these notorious dawdlers can take it easy
...
Analysis of amino acid sequences of the eye lens proteins has confirmed earlier anatomical
evidence indicating that the xenarthrans are an old offshoot of the eutherian stem that arose at
least 75–80 million years ago
...
However, a new classification
has been proposed, which places the two‑toed sloths in the family Megalonychidae and
the three‑toed sloths in the family Bradypodidae
...
2
P74458RA
4
...
They live
high in the canopies of South and Central America and are extremely hard to spot: they are small,
they rarely move and their fur often gets matted with green algae, making them blend in with
the leaves
...
During the dry season the hair of the sloths usually has a dirty brown coloration, but during
long periods of rain it may show a very appreciable greenish tinge brought about by the
increased presence of symbiotic algae
...
Aiello discussed the different
possibilities as to why sloth hair has evolved in such a way to encourage algal colonization
...
Lack of healthy algal colonies could thus provide an explanation why Bradypus does
not survive long in captivity
...
To figure out exactly how slow they are, in 2014, Jonathan Pauli at the University of
Wisconsin‑Madison and his colleagues went to Costa Rica to measure the metabolic rates
of three‑toed brown‑throated sloths and Hoffmann’s two‑toed sloths
...
The
rate at which it expends energy in the wild, known as the field metabolic rate, came in at
162 kilojoules per day per kilogram, meaning it has lower energy needs than any other mammal
that isn’t hibernating, including renowned slouches like koalas (410 kJ/day/kg) and giant pandas
(185 kJ/day/kg)
...
However, whether or not sloths are essential or only incidental to the natural cycle of an
arbovirus, their long experimental viremias are remarkable and Seymour suggests that these
may be due to the animal’s low metabolic rate
...
Louis encephalitis and Oropouche viruses) for which the
role sloths play in the natural cycles is as yet uncertain
...
6
...
They are arboreal folivores,
meaning they live in trees and eat leaves
...
2 per cent of mammal species, and for good reason; leaves tend to be rather difficult to digest
and contain few nutrients
...
P74458RA
3
Turn over
7
...
And they don’t rush digestion
...
That is particularly weird when you
consider that among mammals, the digestion rate typically depends on body size, with big
animals taking longer to digest their food
...
A long and winding alimentary canal isn’t the only way sloths conserve energy
...
Whereas humans hover
within a degree of 38 °C, the three‑toed sloths Pauli studied allowed swings of nearly 5 °C as the
forest cooled or warmed around them
...
9
...
Shivering, favoured by most warm‑blooded animals, is
for creatures with energy to burn
...
Sloths also can’t jump
...
But even beyond saving energy, the sloth’s characteristic slow‑motion upside‑down walking
might have another benefit: camouflage
...
Hanging upside down, completely still, for hours on end seems to do the
trick
...
The constant grip is made possible
by a lattice of tendons in the hands and feet that draw the digits closed while at rest
...
But there seems to be more to their muscular abilities than that
...
An Olympic weightlifter, for instance, has muscles capable of small, powerful movements, whereas
a marathon runner’s muscles are geared towards sustaining long periods of exertion
...
They have an uncanny ability to resist fatigue, as well as a surprising
amount of strength
...
To better understand how they do it, Butcher dissected a dozen sloth cadavers
...
But what muscle there is appears to be extraordinary
...
Box 4
Sloths act as hosts to a wide variety of arthropods, which include biting and bloodsucking
flies such as mosquitoes and sandflies, triatomine bugs, lice, ticks and mites
...
It has been suggested that the sloth moths may receive some protection from avian predators
and possibly find nutrients in secretions of the sloth’s skin and/or the algae present on the
fur
...
They also pointed out that there
is considerable sympatry amongst moth species found on sloths and that several different
species may coexist on the same animal
...
For all these fresh insights, there is still a lot to learn about sloths
...
It doesn’t seem very frugal
...
One thing is clear, though: the more we learn about these extraordinary creatures and
their unhurried lifestyle, the easier it is to appreciate how diet and metabolism can drive
evolutionary adaptation
...
11, Life on Earth: 69-70
the Brazilian Journal of Medical and Biological Research, (2000) 33: 129-146 and (2001) 34: 9-25
...
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Summer 2024
Question Paper Log Number P74458RA
Publications Code 9BN0_03_2406_MS
All the material in this publication is copyright
© Pearson Education Ltd 2024
General Marking Guidance
•
All candidates must receive the same treatment
...
•
Mark schemes should be applied positively
...
•
Examiners should mark according to the mark scheme not according to
their perception of where the grade boundaries may lie
...
All marks on the mark scheme should
be used appropriately
...
Examiners
should always award full marks if deserved, i
...
if the answer matches the
mark scheme
...
•
Where some judgement is required, mark schemes will provide the
principles by which marks will be awarded and exemplification may be
limited
...
Question
number
1(a)
Answer
Additional guidance
Mark
ALLOW to immigrate into a (new) area
ALLOW any term that indicates an area
e
...
environment / habitat
ALLOW other terms in place of species
e
...
plant / animal / organism
(1)
An answer that makes reference to the following:
•
when a species {moves / spreads / grows} into
a new area (1)
ALLOW pioneer species being first to live
in an area
IGNORE dominant species in an area /
species outcompeting other species in an
area
Question
number
1(b)
Answer
Additional guidance
An answer that makes reference to three of the following:
ALLOW auxin for IAA
•
IAA {accumulates on / diffuses / moves to} shaded
side (of shoot) (1)
•
(IAA) regulates the activity of transcription factors (1)
•
causing cell elongation (1)
•
bending the shoot towards the light (1)
ALLOW plant for shoot
ALLOW causing plant to grow
towards the light
ALLOW other words for bending
e
...
leaning
IGNORE move towards / point
towards
Mark
(3)
Question
number
Answer
1(c)(i)
An explanation that makes reference to two of the following:
Additional guidance
Choose an item
...
43 / 42
...
86 / 42
...
8571
(1)
IGNORE any sign
Question
number
Answer
1(c)(iii)
An answer that makes reference to two of the following:
•
(tir1) mutation caused a decrease in the response to IAA (1)
•
plants with mutation produce fewer (lateral) roots (1)
•
because IAA binding to its receptor is required to stimulate
growth of (lateral) roots (1)
Additional guidance
Mark
Choose an item
...
0
•
correct area calculated and recorded as a whole
number (1)
283 / 284
(2)
ALLOW 18
...
5 for diameter
ALLOW area calculated from 18
...
5
given as a whole number
IGNORE units in table
Correct answer with no working gains full
marks
Question
number
Answer
2(b)
A description that makes reference to three of the
following:
Additional guidance
Mark
Choose an item
...
g
...
g
...
(2)
Question
number
Answer
3(a)(i)
An answer that makes reference to the following:
•
Additional guidance
thylakoid (membrane) (1)
Mark
Choose an item
...
•
correct calculation of gradient (1)
Answer between 25 and 28 to any
number of significant figures
•
correct answer to two significant figures (1)
25 / 26 / 27 / 28
Correct answer without working
gains both marks
(2)
Question
number
Answer
Additional guidance
Mark
3(a)(iii)
A description that makes reference to the following:
IGNORE colour of light
Choose an item
...
(3)
ALLOW RUBISCO fixes carbon /
ALLOW RUBISCO catalyses the
reaction between CO2 and RUBP}
Question
number
Answer
Additional guidance
Mark
4(a)
An explanation that makes reference to the following:
ALLOW converse argument for
shark
Choose an item
...
g
...
(4)
•
use different temperatures (1)
ALLOW sensible temperatures or
temperature range (e
...
-5 to 40oC)
•
control of a relevant variable (1)
e
...
abiotic: pH / light intensity /
salt concentration of water / mass
or volume of water / mass
e
...
biotic: age / type / species of
phytoplankton /
•
measure oxygen produced in the light (to estimate
NPP)
ALLOW determine NPP from change
in mass of phytoplankton
•
measure oxygen used in the dark (to estimate
respiration) (1)
Question
number
Answer
4(c)(i)
Choose an item
...
86 : 1
Mark
Additional guidance
Mark
Choose an item
...
8 : 1 and
0
...
09
and 1 : 1
...
•
more {oxygen taken up /carbon dioxide released}
at lower temperature (1)
ALLOW ratio of carbon dioxide
produced to oxygen consumed is
constant /carbon dioxide produced
directly proportional to oxygen
consumed / positive correlation
between oxygen uptake and carbon
dioxide production
•
{more / higher rate of} respiration at {lower
temperature / 14 oC} (1)
•
(mostly) aerobic respiration taking place (1)
ALLOW example e
...
using fats /
proteins as respiratory substrates
•
using respiratory substrates other than
{carbohydrates / glucose} (1)
ALLOW incomplete {aerobic
respiration / oxidation of glucose}
(2)
Question
number
Answer
Additional guidance
5(a)(i)
Mark
Choose an item
...
ALLOW because lipid membrane is
{taken / formed} from the host cell
(membrane)
IGNORE comments about immune
recognition
IGNORE exocytosis
(1)
Question
number
Answer
5(b)
An answer that makes reference to three of the following:
Additional guidance
Mark
Choose an item
...
e
...
2 ÷ 5 = 0
...
1 ÷ 5 = 0
...
9 = 0
...
8 / 2
...
9 / 2
...
(3)
ALLOW enzyme and substrate
concentrations should be the same
(in each experiment) to allow
comparison (of different enzymes)
Question
number
Answer
6(a)(i)
An explanation that makes reference to the following:
•
MDMA binds to serotonin receptors (on the presynaptic membrane) (1)
•
preventing the (re-)uptake of {serotonin /
neurotransmitter} (by presynaptic knob) (1)
•
so more serotonin binds to (receptors on) post
synaptic membrane (1)
•
therefore more action potentials are triggered (in
the post synaptic neurone) / therefore increasing
the rate of transmission of nerve impulses (1)
Additional guidance
Mark
Choose an item
...
(3)
ALLOW the difference
between control and
MDMA group is 8 pushes
ALLOW the difference
between control and
MDMA group is 16 pushes
ALLOW 72% increase
from day 6 to day 10 for
MDMA
Question
number
Answer
6(b)(i)
An answer that makes reference to the following:
•
movement of a substance against a concentration gradient (1)
•
requiring {energy / ATP} (1)
Additional guidance
Mark
Choose an
item
...
g
...
ALLOW decreasing water potential
inside the cell
(3)
•
if sodium ions are taken into the cell the solute
concentration increases inside the cell (1)
•
water (molecules) move into the cell by osmosis (1)
•
(movement of water into the cell) increases the cell
volume (1)
Question
number
Answer
6(b)(iii)
An explanation that makes reference to two of the following:
•
space available to the brain is fixed / (swollen) brain cells take up
more of the available space} (1)
•
(therefore) reducing space available for blood vessels (1)
•
vasoconstriction narrows arterioles (1)
•
(vasoconstriction) reduces {blood flow / pressure} in the brain (1)
Additional guidance
Mark
Choose an item
...
(2)
Question Indicative content
number
*7
Answers will be credited according to candidate's deployment of knowledge and understanding of the material in
relation to the qualities and skills outlined in the generic mark scheme
...
Additional content included in the response must be scientific and relevant
...
A conclusion may be attempted, demonstrating isolated elements of biological knowledge and
understanding but with limited evidence to support the judgement being made
...
A conclusion is made, demonstrating linkages to elements of biological knowledge and understanding, with
occasional evidence to support the judgement being made
...
A conclusion is made, demonstrating sustained linkages to biological knowledge and understanding with
evidence to support the judgement being made
...
(3)
ALLOW eye lens proteins are easily
{obtained / purified / sequenced}
ALLOW more differences in amino
acid sequence the less closely
related the sloths are
ALLOW (the more similarities in
amino acid sequence) the more
closely related
ALLOW sloths with same amino acid
changes belong to same part of
phylogenetic tree
Question
number
8(b)
Answer
Additional guidance
A description that makes reference to four of the following:
Mark
Choose an item
...
g
...
e
...
NaOH / KOH / soda lime
ALLOW spirometer produces a
{trace / graph}
ALLOW description of trace
e
...
peaks and troughs / graph of
tidal volume
•
description of how to obtain rate of oxygen
consumption from trace (1)
•
reference to (using) mass of sloth (1)
•
comment on need to convert oxygen consumption
to kilo joules (1)
Mark
e
...
find slope of peaks / change in
height of peaks divided by time
(4)
Question
number
8(d)
Question
number
8(e)
Answer
Additional guidance
An explanation that makes reference to three of the following:
•
different viruses have {different proteins / different antigens}
(1)
•
antibodies are specific to antigens (1)
•
the virus is specific to sloths if antibodies to the virus are only
found in sloths (1)
•
the virus is incidental to sloths if antibodies to the virus are
found in other species (1)
Answer
Additional guidance
An answer that makes reference to two of the following:
•
plant material is difficult to digest (1)
•
(slow digestive process) allows time for digestive
enzymes to work (1)
•
(slow digestive process) ensures maximum possible
absorption of nutrients (1)
Mark
Choose an item
...
ALLOW difficult to break down
{plant cell (walls) / cellulose / lignin
/ plant fibres}
ALLOW allows more nutrients to be
{absorbed / obtained}
(2)
Question
number
8(f)
Question
number
8(g)
Answer
Additional guidance
An explanation that makes reference to three of the following:
Choose an item
...
g
...
(1)
Question
number
8(h)
Answer
Additional guidance
An answer that makes reference to three of the following:
Mark
Choose an item
...
ALLOW different tertiary structure
ALLOW denature at lower pH
(2)
Question
number
8(j)
Answer
Additional guidance
An explanation that makes reference to two of the following:
•
populations of species that occupy the same habitat (1)
Mark
Choose an item
...
g
...
g
...
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Title: Edexcel a level biology question paper 3 june 2024 salters Nuffield + mark scheme
Description: Mark Scheme (Results) Summer 2024 Pearson Edexcel A Level GCE In Biology A Salters Nuffield (9BN0) Paper 03: General and Practical Applications in Biology
Description: Mark Scheme (Results) Summer 2024 Pearson Edexcel A Level GCE In Biology A Salters Nuffield (9BN0) Paper 03: General and Practical Applications in Biology