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BIOLOGY A

OCR 2024
GCSE Biology A (Gateway Science)
J247/04 (Higher Tier)
With Marking Scheme Merged

Oxford Cambridge and RSA

Friday 7 June 2024 – Afternoon
GCSE (9–1) Biology A (Gateway Science)
J247/04 (Higher Tier)
Time allowed: 1 hour 45 minutes

H

You must have:
• a ruler (cm/mm)
You can use:
• a scientific or graphical calculator
• an HB pencil

*

J

2

4

7

0

4

*

Please write clearly in black ink
...

Centre number

Candidate number

First name(s)
Last name
INSTRUCTIONS
• Use black ink
...

• Write your answer to each question in the space provided
...
The question numbers must be clearly shown
...

• Where appropriate, your answer should be supported with working
...

INFORMATION
• The total mark for this paper is 90
...

• Quality of extended response will be assessed in questions marked with an asterisk (*)
...

ADVICE
• Read each question carefully before you start your answer
...

Write your answer to each question in the box provided
...

A

B

C

D
Which part of the plant cell gives physical protection against disease?

Your answer

© OCR 2024

[1]

Turn over

4
6

The graph shows the changes in chromosome number in a cell during meiosis
...
A is the dominant allele
...

Which statement correctly describes both people?
A They have different genomes but the same genotype
...
C
They have the same genome but different genotypes
...


Your answer

© OCR 2024

[1]

5
8

What is the advantage of sampling using a transect line rather than using random sampling?
A A transect allows changes in the size of populations over time to be seen
...
C
A transect avoids areas which may contain few organisms
...


Your answer

9

[1]

The diagram shows the results of two different crosses of rats
...
Rat 2 is heterozygous
...
Rat 2 is homozygous dominant
...
Rat 1 is homozygous dominant
...
Rat 2 is heterozygous
...

Which function of white blood cells does not require a nucleus?
A Changing shape to squeeze out of capillaries
B Dividing by mitosis after detecting a pathogen
C Producing antibodies which are made of proteins D
Producing enzymes to digest pathogens
Your answer

[1]

11 Lack of food security can lead to people being undernourished
...


The pie chart shows the percentage of undernourished people found in different parts of the
world
...
75 × 10

B

8
6
...
75 × 10

D

9
63 × 10

Your answer

© OCR 2024

[1]

7
12 Bacteria can be genetically engineered to make human insulin
...

Insulin
gene

P

Q

Bacterium
Plasmid

Bacterial plasmid

R

S
Human DNA
Insulin gene

What is the order of these processes in insulin production?
A

P,S,Q,R

B

R,Q,P,S

C

R,Q,S,P

D

S,P,Q,R

Your answer

© OCR 2024

[1]

Turn over

8
13 The diagram shows how monoclonal antibodies (MCA) are used in a test to detect pathogens
...


B

MCA have antibiotics attached that combine with both the test and control antibodies
...


D

The drop contains antibodies that get carried along by the MCA
...


B

Evolution is a random process producing similar structures for different functions
...


D

The limbs have all evolved from a common ancestor to perform the same function
...


Lymphocytes

Antigens
Divide to produce plasma cells

Antibodies secreted

Cell X

Antigens destroyed
by antibodies

What is the function of cell X?
A

Cell X will live for many years and engulf foreign bacteria and viruses
...


C

Cell X will respond rapidly if the antigen reinfects the body again
...


Your answer

© OCR 2024

[1]

11
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

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12
Section B

16 The St Lucia racer is the rarest snake in the world
...
The diagram shows a food web from St Lucia
...
[1]

(b) Mongooses are described as both predators and competitors of St Lucia racers
...


...


...
[2]

(c) Biomass is lost as it passes through this food web
...

egestion

growth

photosynthesis

respiration
[1]

© OCR 2024

13
(d) Mongooses were introduced into St Lucia by farmers to control pests in their fields
...

Abiotic control
Biological control
Chemical control
Genetic control
[1]

(ii) The mongooses soon spread throughout St Lucia
...

The St Lucia racer lays about 5 eggs each year
...


...
[1]

(e) By 1973 the St Lucia racers were thought to be extinct but a small number were found on a small
island off the coast of St Lucia
...

(i)

Suggest why these snakes have survived on the island
...


...


...


...

(a) Which is a correct statement about antiseptics and antibiotics?
Tick (3) one box
...

Antibiotics are used inside the body, but antiseptics are not
...

Antibiotics are used on non-living tissue and antiseptics on living tissue
...

Some students do an experiment to see how well four different disinfectants (A, B, C and D) kill
bacteria
...

Pour each of the mixtures into separate Petri dishes and allow to set
...

Put each Petri dish in an incubator
...


...


...

Explain why
...


...
[2]

© OCR 2024

15
(c) The diagrams show the Petri dishes after 3 days
...

1
...

2
...

[2]

(ii) One of the students said that disinfectant A is equally effective at killing bacteria as
disinfectant B
...


...


...
[2]

© OCR 2024

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16
18 In many areas, the number of elephants living in Africa is decreasing
...

The table shows how the number of elephants in Africa has changed
...
3 million

1989

2015

600 000

400 000

(a) Calculate the percentage decrease in the population size between 1979 and
2015
...


Percentage decrease =
...

Dropping at a decreasing rate
Dropping at a steady rate
Dropping at an increasing rate
[1]
(c) In some areas of southern Africa, elephants are very important for ecotourism
...


...


...
[2]

© OCR 2024

17
(ii) In ecotourism areas, elephant numbers are increasing
...

Scientists therefore want to control the population size
...


•

Relocation – elephants are moved to a country where their numbers have dropped
...


Suggest one disadvantage for each of these methods
...


...


...


...
This involves injecting antibodies which block the sperm receptor sites on eggs
...


...
[1]

© OCR 2024

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18
(d)* In East Africa, elephants are hunted for their tusks
...


Explain why the number of tuskless elephants is rapidly increasing in East Africa
...


...


...


...


...


...


...
[6]

© OCR 2024

19
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

Turn over

20
19 Mistletoe is a green plant that is often seen growing high in a tree in winter
...

It therefore needs to act as a parasite on the tree
...

competitor

host

mutualistic partner

prey
[1]

(b) Explain why the mistletoe grows into the phloem of the tree
...


...


...
One species of
mistletoe has greener leaves than the other
...

The carbon dioxide is not supplied to the mistletoe
...


The table shows their results
...
4

39

Eastern mistletoe

0
...


...


...
[2]

(ii) Explain the relationship between the chlorophyll content and the percentage of radioactive sugar
in each species of mistletoe
...


...


...


...

They can cause the milk to decompose
...

Some students investigate the effect of temperature on the decomposition of milk
...

Keep each beaker in a water bath at a different temperature: 15 °C, 25 °C and 35 °C
...


•
•
•

The table shows their results
...
5

6
...
3

6
...
8

25

6
...
3

6
...
9

5
...
5

6
...
1

5
...
9

(a) Explain why the students measured the pH of the milk
...


...


...


...


...


...


...


...


...

Predict what effect this would have on the results
...

Prediction
...

Explanation
...


...

(a) Experiments have shown that significant doses of acrylamide can cause cancer in animals
...


...


...

Other scientists are not sure about the effect of acrylamide on humans, despite the results of
the animal experiments
...


...
[1]

(b) Scientists measured the concentration of acrylamide in toast made from three different types of
bread: potato, wheat and rye
...

700

Key:
Potato

600

Wheat

Concentration of
acrylamide
(mg / kg of bread)

500

Rye

400
300
200
100
0
Untoasted

Light

Medium

Colour of toast

© OCR 2024

Dark

25
(i)

Give two conclusions that the scientists could make from their investigation
...


...


...
A slice of toast has a mass of 50 g
...

Calculate the maximum number of whole slices of toast the person can eat without exceeding
the recommended maximum intake
...


Number of whole slices =
...


...
[1]

© OCR 2024

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26
(c) During toasting, acrylamide is made from a chemical called asparagine
...
The gene coding
for asparagine synthetase needs to be switched on by other proteins
...

Use words from the list
...

When a gene is expressed,
...

The mRNA then moves to the
...

[4]
(ii) Scientists want to produce a variety of wheat that contains less asparagine
...

Describe the difference between this process and genetic engineering
...


...
[1]

© OCR 2024

27
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

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28
22 The table shows some details of three genetic diseases that can affect humans
...

The mutation prevents a muscle protein
being made
...


(a) There are 66 million people in the UK
...


Number of cases =
...

Explain why each of these diseases cause difficulty in moving the legs
...


...


...


...

Use the information in the effect column of the table
...


...


...

Describe two risks of using stem cells to treat patients
...


...


...
You must write the question numbers clearly
in the margin
...


...


...


...


...


...


...


...


...


...


...


...


...

© OCR 2024

31

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...


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...


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...
OCR qualifications include
AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals, Functional Skills,
Key Skills, Entry Level qualifications, NVQs and vocational qualifications in areas such as IT,
business, languages, teaching/training, administration and secretarial skills
...
OCR is a not-for-profit organisation; any surplus made
is invested back into the establishment to help towards the development of qualifications and
support, which keep pace with the changing needs of today’s society
...
It shows the basis on which marks were awarded by examiners
...

All examiners are instructed that alternative correct answers and unexpected approaches
in candidates’ scripts must be given marks that fairly reflect the relevant knowledge and
skills demonstrated
...

© OCR 2024

Oxford Cambridge and RSA Examinations

J247/04

Mark Scheme

June 2024

MARKING INSTRUCTIONS
PREPARATION FOR MARKING
RM ASSESSOR
1
...


2
...
These are available in RM Assessor
...


Log-in to RM Assessor and mark the required number of practice responses (“scripts”) and the required number of standardisation
responses
...


Mark strictly to the mark scheme
...


Marks awarded must relate directly to the marking criteria
...


The schedule of dates is very important
...
If you experience problems, you must contact your Team Leader (Supervisor) without delay
...


If you are in any doubt about applying the mark scheme, consult your Team Leader by telephone, email or via the RM Assessor messaging
system
...


Crossed Out Responses
Where a candidate has crossed out a response and provided a clear alternative then the crossed out response is not marked
...


2

J247/04

Mark Scheme

June 2024

Rubric Error Responses – Optional Questions
Where candidates have a choice of question across a whole paper or a whole section and have provided more answers than requir ed, then
all responses are marked and the highest mark allowable within the rubric is given
...
(The underlying assumption is that the candidate has penalised themselves
by attempting more questions than necessary in the time allowed
...
When a question requires candidates to select more than one option/multiple options, then local marking arrangements need to
ensure consistency of approach
...

Short Answer Questions (requiring only a list by way of a response, usually worth only one mark per response)
Where candidates are required to provide a set number of short answer responses then only the set number of responses should be marked
...
The remaining responses should not then be marked
...
(The underlying assumption is that the candidate
is attempting to hedge their bets and therefore getting undue benefit rather than engaging with the question and giving the m ost
relevant/correct responses
...
)

3

J247/04

Mark Scheme

June 2024

Longer Answer Questions (requiring a developed response)
Where candidates have provided two (or more) responses to a medium or high tariff question which only required a single (deve loped) response
and not crossed out the first response, then only the first response should be marked
...

6
...
If the
candidate has continued an answer there then add the annotation ‘SEEN’ to confirm that the work has been seen
...


Award No Response (NR) if:
•

there is nothing written in the answer space

Award Zero ‘0’ if:
• anything is written in the answer space and is not worthy of credit (this includes text and symbols)
...

8
...
Please refer to these
comments when checking your practice responses
...

If you have any questions or comments for your Team Leader, use the phone, th e RM Assessor messaging system, or email
...


Assistant Examiners will send a brief report on the performance of candidates to their Team Leader (Supervisor) via email by the end of the
marking period
...
Constructive
criticism of the question paper/mark scheme is also appreciated
...


Mark Scheme

June 2024

For answers marked by levels of response:
Read through the whole answer from start to finish, using the Level descriptors to help you decide whether it is a strong or weak answer
...
Using a ‘best-fit’ approach based on the skills and science content evidenced
within the answer, first decide which set of level descriptors, Level 1, Level 2 or Level 3 , best describes the overall quality of the answer
...

The lower mark should be awarded where the level descriptor has been evidenced but aspects of the communication statement (in italics)
are missing
...

The communication statement determines the mark within a level
...


5

J247/04

11
...


Annotation

Meaning

/

alternative and acceptable answers for the same marking point



Separates marking points

DO NOT ALLOW

Answers which are not worthy of credit

IGNORE

Statements which are irrelevant

ALLOW

Answers that can be accepted

()

Words which are not essential to gain credit

__

Underlined words must be present in answer to score a mark

ECF

Error carried forward

AW

Alternative wording

ORA

Or reverse argument

7

J247/04
12
...
This mate rial includes:
•

the specification, especially the assessment objectives

•

the question paper

•

the mark scheme
...

You should ensure also that you are familiar with the administrative procedures related to the marking process
...
If you are examining for the first time, please read carefully Appendix 5 Introduction to Script Marking:
Notes for New Examiners
...
Your first point of contact is your Team Leader
...


AO1
...


AO1
...

Apply knowledge and understanding of scientific ideas and scientific enquiry, techniques and procedures
...
1

Apply knowledge and understanding of scientific ideas
...
2

Apply knowledge and understanding of scientific enquiry, techniques and procedures
...
1

Analyse information and ideas to interpret and evaluate, make judgements and draw conclusions and develop and improve
experimental procedures
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


9

J247/04

Mark Scheme

June 2024

For answers to Section A if an answer box is blank ALLOW correct indication of answer e
...
circled or underlined
...
1

2

B

1

1
...
1

4

B

1

1
...
1

6

B

1

2
...
1

8

B

1

1
...
1

10

A

1

1
...
1

12

D

1

1
...
1

14

C

1

2
...
1

Guidance

ALLOW 4

J247/04

Mark Scheme

Question
16

Answer



Two / 2

(a)
(b)



(Idea they are Predators) because they hunt/eat the
racers/snake

(c)
(d)

(i)
(ii)



(i)

AO
element

1
2

2
...
1

Guidance
IGNORE lizard and frog
ALLOW racers are its prey

(Idea they are competitors because) they both feed on
lizards / eat the same food

DO NOT ALLOW both feed on lizards and frogs



Egestion and respiration

Biological control

Idea Mongooses produce more offspring and would



(The snakes survived because) there was no/less
mongoose/predator

(ii)

Marks

IGNORE predators of snakes/racers
ALLOW they are both predators of lizards

eat/predate the racer/snake

(e)

June 2024





1
...
1
2
...
1b

ALLOW mongooses produce more offspring and
eat the racer’s/snake food/lizard
ALLOW mongooses produce more offspring and
outcompete the snake
ALLOW mongoose produce 9 offspring where
snake produces 5 / 4 more offspring to eat the
snake/racer
ALLOW no/less competition / not/less eaten by the
mongoose

Any two from:
Mongoose could reach the island



(Tourists) could destroy
habitat/poach/eat/hunt/kill/predate snake

2



They could eat/hunt/kill/predate/the remaining snakes

Introduce disease/pathogens

1



2 x 3
...
g
...
1
DO NOT ALLOW more than one box ticked

2

2 x 1
...
2



Allow oxygen to enter the dish / prevent anaerobic
conditions

June 2024



Stop pathogens/harmful bacteria
growing/reproducing/created /
Otherwise, pathogens/harmful bacteria could

ALLOW (for bacteria) to carry out aerobic
respiration
ALLOW stop anaerobic bacteria from growing = 2

grow/reproduce/create

ALLOW bacteria need oxygen to carry out aerobic
respiration = 2



OR
Stops oxygen to enter the dish / anaerobic conditions

Pathogens/harmful bacteria grow/reproduce



(c)

ALLOW pour solution with bacteria over the agar
ALLOW use a spreader / rod / swab / pipette /
cotton buds
ALLOW idea of aseptic technique
ALLOW ECF for incorrect named wire/loop


(lack of oxygen, bacteria) can’t carry out aerobic
respiration bacteria

(i)

2
Idea that B is the most effective/killed the most/removed



all the bacteria

2 x 3
...
3b

Guidance

IGNORE amount





Using different concentrations/amounts of bacteria

June 2024



IGNORE stronger bacteria




ALLOW repeat for one mark if no marks are
awarded
IGNORE reference to time

13

J247/04

Mark Scheme

Question
18 (a) (i)

AO
Marks element
3

Answer
First check the answer on the answer line
If answer = (-)69 (%) award 3 marks
(900 000 ÷ 1 300 000) × 100

June 2024



2 x 2
...
9 ÷ 1
...
2307692 for 2
marks

1
...
23077(%)

(-)69 (%)

(b)
(c)

(i)



Dropping at a decreasing rate 
Idea to see (threatened) habitats/(endangered)
species/ecosystems/nature

1
2



To raise money/employment/profit/donation



14

Guidance

2
...
1

J247/04

Mark Scheme

Question
(ii)

AO
Marks element
3
3 x 2
...




(iii) This method is not swallowed/orally/ingested / the
(contraceptive) pill is taken orally/swallowed
OR
This method does not use hormones / (contraceptive) pill
uses hormones
OR
This method allows egg to mature/release/ovulation /
contraceptive pill prevents egg
maturing/release/ovulation

Guidance



1

2
...

Level 3 (5–6 marks)
Detailed explanation why the number of tuskless
elephants is rapidly increasing in East Africa using ideas
of both inheritance and natural selection
...
The information presented is
relevant and substantiated
...

AND
Explains why the spread of this allele may have negative
effects on the elephant population
There is a line of reasoning presented with some
structure
...

Level 1 (1–2 marks)
Explanation why the number of tuskless elephants is
rapidly increasing in East Africa using ideas from either
inheritance or natural selection
...
1 AO1
...
1 understanding of scientific ideas to explain
2 x 3
...

Inheritance:
• Dominant allele is always expressed if
present
• Only one tuskless allele needed to give
phenotype/for elephant to be tuskless
AO2
...

Inheritance:
• 50% chance of offspring inheriting this allele (if
mother is tuskless)
• 50% chance of female elephants born with
tusks (if mother is tuskless)
• only females born tuskless
• 100% of male elephants born with tusks / 0%
male elephants born with no tusks (if inherit
dominant allele)
• Males can only survive as homozygous
recessive
• Accept correct Punnett square showing
heterozygous x homozygous recessive
Natural selection:
• Tuskless elephants are less likely to be
hunted ORA
• The tuskless elephants are more likely to
survive and breed ORA
• The allele for tuskless is more likely to be
passed on ORA
• The frequency of the tuskless allele will
increase in the population over time
• No males born without tusks

J247/04

Question

Mark Scheme
AO
Marks element

Answer
There is an attempt at a logical structure with a line of
reasoning
...

0 marks
No response or no response worthy of credit
...
2a Analyses information to explain why
the spread of the allele may have negative
effects
...

• Idea tusks are used to access food

J247/04

Mark Scheme

Question
19

Host

(a)
(b)





Answer

Gains sugars (from the tree/phloem)



Sugar is transported in the phloem

(c)

(i)



Marks

AO
element

1
2

1
...
1

1
...
1

2
...
2a

IGNORE simple quoting of data
ALLOW ORA
AW radioactive carbon/carbon dioxide for sugar
ORA for Eastern mistletoe/more chlorophyll

sugar/glucose/photosynthesise

ORA for Eastern mistletoe/more chlorophyll
IGNORE ATP

18

J247/04

Mark Scheme

Question
20

(a)

Answer



Lactic acid alters/lowers pH



To measure the speed/rate of decomposition/decay

(b)



Any three from:

June 2024

Marks

AO
element

2

2 x 2
...
2



Draw a line/scatter graph

Put time on the x axis



Put pH on the y axis



Draw three lines, one for each temperature

(c)



(Increase in temperature) increases the kinetic energy

(d)

ALLOW separate colours/key for each
temperature
IGNORE line of best fit
ALLOW time and pH alone but not stated which
axis for max 1 mark if no marks awarded
3



(increase in temperature) more collisions



1 x 3
...
2

1 x 3
...
3a

ALLOW (increasing the temperature) will increase
conversion of sugar into lactic acid
DO NOT ALLOW decay stops at high
temperatures
ALLOW increase energy to move around / move
faster
IGNORE more energy
ALLOW more enzyme substrate complexes
ALLOW pH will be 6
...
1



Cause mutations/change DNA/genes

Rapid/uncontrolled (cell) division

Form tumours
(ii)
(b)

(i)



AW cell replication/multiplication/mitosis
IGNORE reproduction/uncontrolled growth



Idea results in humans might be different / only tested on
animals



Any two from:

1
2

2
...
2b

Longer heating/dark toast produces highest
concentration/more acrylamide



IGNORE spread to surrounding tissue
IGNORE humans eat toast with no effects /
humans have not been tested
AW concentration for acrylamide
ALLOW as toasting increases, acrylamide



The concentration of acrylamide in light coloured toast is

increases
ALLOW untoasted and light rye make the least
acrylamide
ALLOW lightly toasted has no effect on

very similar/same as untoasted bread

acrylamide

Toast made from potato has the most acrylamide







Heating/as bread darkens wheat has the least increase in

ALLOW any other correct conclusion between
wheat and rye qualified



acrylamide

(ii)

Guidance

First check the answer on the answer line
If answer = 6 award 3 marks
(Dark potato toast =) 600 (mg/kg)

(One slice has) 30 (mg)

Maximum = 6 slices




3

3 x 2
...
2

Answer of 6
...
1

1

1
...
2

Guidance

ALLOW any correct calculating method
ALLOW 660

OR
66 000 000 / 100 000 x 12





= 7920
(b)

3

1
...
1

(Huntington’s) prevents/reduces the cerebrum/brain

AW signals throughout
ALLOW spinal cord can receive less impulses

sending impulses (to move the legs)

ALLOW brain sends impulses to spinal cord



(MD) cannot contract muscles/effectors (to move the
legs)

ALLOW muscles contract to move legs





(SMA) prevents/less impulses being carried by motor
neurones

ALLOW prevents/less impulses reaching
muscles/effectors
ALLOW motor neurones send impulses to
muscles/effectors



22

J247/04

Question
(c)

Mark Scheme

Answer
Huntington’s/dominant as it produces a protein and MD &
SMA/recessive because it doesn’t produce a protein (that
causes the disease)

Marks
2

June 2024
AO
element
2 x 2
...




OR
Both alleles would need to be affected to have the

ALLOW need both (affected) alleles to be

disorder in MD & SMA

expressed when it is recessive



(d)



Any two from:
Rejection (of cells)

2



New cells would be damaged again by protein/not work

2 x 1

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