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COMBINED SCIENCE A

OCR 2024
GCSE Combined Science A
(Gateway Science)
J250/02 Biology (Foundation Tier)
With Marking Scheme Merged

Oxford Cambridge and RSA

Friday 7 June 2024 – Afternoon
GCSE (9–1) Combined Science A
(Gateway Science)
J250/02 Biology (Foundation Tier)
Time allowed: 1 hour 10 minutes

F

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

*

J

2

5

0

0

2

*

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 60
...

• 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
...
Which piece of scientific equipment will they use?
A Balance B
pH probe C
Pooter D
Quadrat
Your answer

© OCR 2024

[1]

3
3

Scientists test the effect of new drugs on the growth of a pathogen
...

Which of these are examples of continuous variation?

A Eye colour and height
B Eye colour, height and weight C
Height and weight
D Height only

Your answer

© OCR 2024

[1]

Turn over

4
6

Which process is required to recycle both carbon and
nitrogen? A Condensation
B Decomposition C
Photosynthesis

D

Precipitation
Your answer

7

[1]

Which risk is decreased by using adult stem cells instead of embryonic stem cells in skin
transplants?
A Fatty deposits forming below the skin B
Rejection of transplanted skin
C Skin becomes less waterproof D
Skin cancer developing
Your answer

© OCR 2024

[1]

5
8

The diagram shows a phylogenetic tree for a group of related
animals
...
Which change would increase biodiversity?
A Adding chemical fertilisers to a grass lawn B
Cutting a grass lawn more often than usual
C Removing a grass lawn area and putting down paving stones D
Replacing a grass lawn area with a wild flower meadow
Your answer

© OCR 2024

[1]

Turn over

6
10 Which row is a correct comparison of meiosis and mitosis?
Involves cell
division

Halves the number
of chromosomes

Requires DNA
replication

A

both

meiosis only

both

B

both

both

both

C

meiosis only

both

mitosis only

D

mitosis only

meiosis only

mitosis only

Your answer

© OCR 2024

[1]

7
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

Turn over

8
Section B
11 Inheritance is passing genetic material from one generation to the next
...

Term

Definition

a change in the structure of DNA

Chromosomes

Mutation

different versions of the same gene

nucleus containing two different genes

strands of DNA containing genes
[2]
(b) Which terms describe sex cells in humans?
Tick (✓) two boxes
...

Pea
Pea pod

Pea pods can be green or yellow
...
All the pods on the new plant are green
...

Use words from the list
...
and the

allele for yellow is
...
This means it is
...

[3]
(ii) The new plants with green pods are then crossed
...

green pods
G
green pods

g

G
g

Probability =
...


(a) Complete the sentences about powdery
mildew
...

bacterium

chlorophyll

decrease

fungus

increase

threat

virus

wind

Powdery mildew is caused by a pathogen that is a
...

The powdery mildew covers the leaves which could result in less light being absorbed by

...
the spread of the
disease
...
[1]

(c) Describe how selective breeding is used to make plants resistant to powdery mildew
...


...


...
[3]

© OCR 2024

11
13 New medicines are developed all the time
...
The human stomach contains an enzyme that
is specific to proteins like insulin
...


...


...
[2]

(b) Which type of medicine has been developed to treat HIV?
Put a ring around the correct option
...

Complete these sentences about cardiovascular disease
...
low in saturated fat
...
muscle in the ventricle wall
...

A student investigates the moisture content of different
soils
...

Place the soil samples in a warm oven to dry for 4 hours
...


The table shows their results
...
1

97
...
2

125
...
3

121
...


...


(a)
(i) Calculate the change in mass for each soil sample
...

Give all answers to the same number of decimal places
...

Suggest why the student cannot make a fair comparison between the samples
...


...

1
...

2
...

[2]
© OCR 2024

13
(b) Explain how low moisture content in soil affects transpiration in plants
...


...


...
[3]

(c) Moisture content is one abiotic factor that affects plants
...

1
...

[2]

© OCR 2024

Turn over

14
15* The graph shows the changes in population of a predator and its prey
...

Identify the predator and the prey using evidence from the graph to support your choice
...


...


...


...


...


...


...

(a) In an investigation, scientists estimated the population of flying insects in a forest
...

The mass of insects collected each month is then recorded
...


The table shows their results
...

Both years should be included on the same grid
...


May

June

July

Aug

Sept

Month
[4]
© OCR 2024

17
(ii) What two conclusions can be made about the mass of flying insects in 1995 compared to 2015?
1
...

2
...

[2]
(iii) How can the scientists’ method be developed to investigate biodiversity in the
forest? Tick (✓) one box
...

Record the number of different species found in the nets
...

Use their data to calculate mean mass for each year
...

The scientists trap insects using a pitfall trap
...

For each estimate they use this method:
•
•
•
•

Place pitfall traps in different areas of the forest
...

Mark the insects
...


A week later they trap a second sample of insects
...

State one other precaution that they should take when deciding how to mark the insects
...


...
This table shows the results
of this investigation
...

Use the formula to estimate the population size of insects in 2015
...


Estimated population of insects =
...

The population of insects living on the forest ground increased between 1995 and 2015
...

True

False

Both investigations came to the same conclusion about
changes in insect population
...

Only one investigation shows how the insect population
changes with each month
...

[2]

END OF QUESTION PAPER
© OCR 2024

19
EXTRA ANSWER SPACE
If you need extra space use these lined pages
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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

J250/02

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
...


Mark Scheme

June 2024

Work crossed out:
a
...


if a candidate crosses out an answer to a whole question and makes no second attempt, and if the inclusion of the answer does not
cause a rubric infringement, the assessor should attempt to mark the crossed out answer and award marks appropriately
...


Always check the pages (and additional objects if present) at the end of the response in case any answers have been continued there
...


7
...
Award NR (No Response)
-if there is nothing written at all in the answer space
-OR if there is a comment which does not in any way relate to the question (e
...
‘can’t do’, ‘don’t know’)
-OR if there is a mark (e
...
a dash, a question mark) which isn’t an attempt at the question
...


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
...


4

J250/02

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

6

J250/02
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
...


8

J250/02

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

D

1

1
...
2

4

B

1

1
...
1

6

B

1

1
...
1

8

D

1

2
...
1

10

A

1

1
...
1

Answer

Guidance

✓✓

Gamete

(b)

✓
2

Specialised
(c)

(i)

Dominant
Recessive

Three ticked and two correct = 1 mark
Three ticked and one correct = 0 marks

✓
3

3 x 2
...
1

✓

Heterozygous
(ii)

2 x 1
...
25

✓
ALLOW ECF from genotypes in genetic diagram

10

J250/02

Mark Scheme

Question
12

(a)

Fungus
Wind

Decrease

4 x 1
...
1

✓

✓

It can be spread/transmitted (between organisms) /

Caused by a pathogen

(c)

4

Guidance

✓

Chlorophyll

(b)

AO
Marks element

Answer

✓

June 2024

✓
ALLOW caused by fungus/microorganisms
IGNORE germs

Plant(s) that are (most) resistant are chosen
These plants are crossed/bred

✓
3

✓

Process repeated / process continued over many
generations

ALLOW it can be passed on / it can be caught / it
is contagious
IGNORE it can be shared

✓

11

3 x 1
...
1 IGNORE disintegrate/destroy

The insulin would not enter the blood / insulin would not

IGNORE references to stomach acid
IGNORE the insulin will not reach the blood stream

reach the liver

so easily/quickly

(b)

Antiviral

(c)

Diet

✓

✓
1

1
...
1
1
...
8, 28
...
0 award 2 marks

Marks
2



120
...
3 and 154
...
5 and 126
...
3

= 22
...
7, 5
...
2
2
...
1b

2

2 x 3
...
8, 28
...
1



Less water evaporates/lost from the leaves

Less water absorbed (by the roots)
Less transpiration / transpiration reduced

Less water moved up the stem/xylem/plant

Guidance

ALLOW transpiration may stop
ALLOW water not evaporated/lost from the leaves
ALLOW water not absorbed
ALLOW water not moved up the stem/xylem/plant
IGNORE no water supply





Stomata (may) close
Plant (may) wilt

(c)

Any two from:

Light (intensity)

2



DO NOT ALLOW biotic factor e
...
,
predation/food/nutrients/disease
IGNORE just sun



Temperature
Soil pH

Minerals

2 x 1
...
g
...
1 AO2
...
1a describe the patterns
2 x 3
...

Level 3 (5–6 marks)
Detailed description and explanation of a pattern in the
graph, including identifying both the predator and the
prey using clear evidence
There is a well-developed line of reasoning which is clear
and logically structured
...

Level 2 (3–4 marks)
Description and explanation of a pattern shown by the
graph
OR
Identifies the predator and the prey using clear evidence
There is a line of reasoning presented with some
structure
...


AO3
...
The information is in the most part relevant
...
2a Analyse information and ideas make
judgments about predator and prey
Lions are predators because
• their numbers are lower / because their
numbers peak after the gazelle / when lion
numbers are increasing, gazelle numbers are
decreasing

0 marks
No response or no response worthy of credit
...
2 Place ticks and crosses on right hand side of
grid
Minimum 50% of grid used
Scale must be in ascending order and linear
ALLOW the use of an axis break

Y axis labelled with units

Accurate bars drawn

June 2024



2



Pattern across the months is the same

2 x 3
...
g
...
Must refer to both years
ALLOW reference to comparisons in the patterns
of numbers/population of insects



17

J250/02

Mark Scheme

Question
Answer
(iii) Record the number of different species found in the nets

Marks
1



(b)

(i)

Any one from:

1

June 2024

AO
element
3
...
2

Idea that mark must not make it more visible to predators

ALLOW mark not visible to predators /
doesn't make it more likely they get eaten by
predators / do not use bright ink
DO NOT ALLOW so it is visible
BUT ALLOW only visible under UV light
IGNORE make sure it is marked in the same place

Idea that mark should not be toxic or poisonous (to the

ALLOW does not cause harm (to the insect /
predator)
IGNORE does not affect (the insect)
IGNORE not too much paint or ink / different
colours





insect)

ALLOW answers in terms of questions e
...
,
will it make it visible to predators?
will it harm the insect?
(ii)

First check the answer on the answer line
If answer = 1530 award 2 marks
146 x 63
6

False
False
True
True

2 x 2
...
figs)

(c)

2


2



18

2 x 3

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