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COMBINED SCIENCE A

OCR 2024
GCSE Combined Science A
(Gateway Science)
J250/07 Biology (Higher Tier)
With Marking Scheme Merged

Oxford Cambridge and RSA

Friday 10 May 2024 – Morning
GCSE (9–1) Combined Science
A (Gateway Science)
J250/07 Biology (Higher Tier)
Time allowed: 1 hour 10 minutes

H

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

*

J

2

5

0

0

7

*

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 row shows the correct information about insulin?

Organ that produces insulin

Type of signal

Target organ

A

liver

chemical

pancreas

B

liver

electrical

pancreas

C

pancreas

chemical

liver

D

pancreas

electrical

liver

Your answer
2

[1]

The length of a bacteria cell is 5
...
What is the length of this cell in
mm? (1 mm = 1000 µm)
–6
A 5
...
3 × 10
3
C 5
...
3 × 10
Your answer

© OCR 2024

[1]

3
3

What are two characteristics of a cell membrane?
A Non-selective barrier and contains plasmids B
Non-selective barrier and contains receptors C
Selective barrier and contains plasmids
D Selective barrier and contains receptors

Your answer

4

[1]

The diagrams show stages in the hypothesis used to explain the mechanism of enzyme
action
...
B
Only embryonic stem cells can differentiate
...
D
There are more ethical issues in the use of adult stem cells
...

Our eyes only detect light with a wavelength greater than 400 nm
...
2 µm
B ~0
...
4 µm
D >0
...


Blood vessel T

Blood vessel S

Which statement about these blood vessels is correct?
A

Blood flows through blood vessel T at a slower rate
...


C

Blood vessel T has a larger lumen diameter
...


Your answer

© OCR 2024

[1]

5
8

The table shows some information about respiration
...

B Only DNA replication occurs inside sub-cellular structures
...

D Only mitosis is part of the cell cycle
...
The pH inside the stomach of the human digestive system is between pH 1 and pH 2
...


Enzyme P
Enzyme Q
Enzyme activity

2

4

6

8 10 12 14
pH

Which statement about the enzymes is correct?
A

Both enzymes would be denatured inside the small intestine
...


C

Neither enzyme would work at its highest activity inside the stomach or small intestine
...


Your answer

© OCR 2024

[1]

7
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

Turn over

8
Section B
11 Fig
...
1 and Fig
...
2 show two different transport vessels in plants
...
11
...
11
...

Give two reasons why Fig
...
2 shows phloem vessels
...


...


...


...


...


...


...
They want to find out if
the enzyme breaks down the starch into sugar
...

Leave the mixture for 5 minutes
...

Place the boiling tube in a hot water bath
...


Benedict’s solution is a blue solution that, when heated, forms a coloured precipitate if sugar
is present
...
12
...

Fig
...
1

Boiling tube
Mixture
and
Benedict’s
solution

Hot water

(a) The teacher repeats the method with different enzymes
...


...

Hazard
...


...
12
...

Fig
...
2
Blue

0
...
5

1
...
5

2
...
5

3
...
5

Concentration of sugar (%)
The table shows the results recorded by the student
...


...
5 – 3
...


(i) Complete the table
...

How can the student tell that it is not an accurate value?

...

The graph compares absorbance with the percentage of sugar
concentration
...
4
1
...
0
0
...
6
0
...
2
0
...
They record an absorbance of 0
...

Use the graph to find the sugar concentration of mixture C
...
% [1]
(ii) The answer to (i) is outside the range stated in the results table
...


...
[1]

© OCR 2024

Turn over

12
13 A student investigates diffusion
...
This is the method they use:
•
•
•
•

Cut the agar into cubes of different sizes
...

Add dilute hydrochloric acid to each boiling tube
...


The diagram shows one of their boiling tubes when the agar cube has started to turn yellow
...


Agar

Length of

cube

one side
(cm)

Surface area
(cm2)

Volume
(cm3)

Surface

Time taken

area to

to turn

volume
ratio

yellow
(seconds)

A

1

6

1

6:1

320

B

2

24

8

3:1

552

C

3

D

4

96

64

1
...
2:1

1145

F

6

216

216

1:1

1408


...

Write your answer in the table
...

(i)

Identify this anomalous result
...
[1]

(ii) The anomaly was due to random error
...


...


...


...


...

Fig
...
1 shows the reflex arc involved in blinking
...
14
...

Use Fig
...
1
...


...


...


...
[4]

(b) The endocrine system also controls the body
...
[1]

(ii) Describe two effects of adrenaline on the human body
...


...


...

Explain how the progesterone contraceptive pill prevents pregnancy
...


...


...


...

Fig
...
2 shows the results when three meals were included in the computer model
...
14
...


...


...


...
[2]

(iii) Compare the functions of glucagon and hormone Y
...


...


...


...

Oxygen bubbles

Water

Pondweed

Lamp

The number of oxygen bubbles released each second indicates the rate of photosynthesis
...

They use their result to correctly calculate a rate of 0
...

How many bubbles did the student count in the 2 minutes?

Number of bubbles =
...

Describe how they should develop their investigation
...


...


...


...


...


...


...
[6]

© OCR 2024

Turn over

20
16
(a) The diagram shows drawings of red blood cells
...

1
...

2
...

[2]

© OCR 2024

21
(b) This diagram shows a frog heart
...


...
[1]

(ii) Explain why the structure of the frog heart makes it less efficient than a human heart
...


...


...
[3]

END OF QUESTION PAPER

© OCR 2024

22
EXTRA ANSWER SPACE
If you need extra space use these lined pages
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© OCR 2024

24

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Higher
GCSE
Combined Science Biology A Gateway Science
J250/07: Paper 7 (Higher Tier)
General Certificate of Secondary Education

Mark Scheme for June 2024

Oxford Cambridge and RSA Examinations

OCR (Oxford Cambridge and RSA) is a leading UK awarding body, providing a wide range of
qualifications to meet the needs of candidates of all ages and abilities
...


It is also responsible for developing new specifications to meet national requirements and
the needs of students and teachers
...

This mark scheme is published as an aid to teachers and students, to indicate the requirements
of the examination
...
It does not
indicate the details of the discussions which took place at an examiners’ meeting before
marking commenced
...

Mark schemes should be read in conjunction with the published question papers and the
report on the examination
...


Make sure that you have accessed and completed the relevant training packages for on-screen marking: RM Assessor Online Training; OCR
Essential Guide to Marking
...


Make sure that you have read and understood the mark scheme and the question paper for this unit
...


3
...


MARKING
1
...


2
...


3
...
It is essential that you meet the RM Assessor 50% and 100% (traditional 50% Batch 1 and
100% Batch 2) deadlines
...


4
...


5
...
Where no
alternative response has been provided, examiners may give candidates the benefit of the doubt and mark the crossed out response where
legible
...
Enter a mark for each question answered into RM
assessor, which will select the highest mark from those awarded
...
)

Multiple Choice Question Responses
When a multiple choice question has only a single, correct response and a candidate provides two responses (even if one of these responses
is correct), then no mark should be awarded (as it is not possible to determine which was the first response selected by the candidate)
...


Contradictory Responses
When a candidate provides contradictory responses, then no mark should be awarded, even if one of the answers is correct
...

The response space should be marked from left to right on each line and then line by line until the required number of responses have been
considered
...
Examiners will have to apply judgement as to whether a ‘second response’
on a line is a development of the ‘first response’, rather than a separate, discrete response
...
)

Short Answer Questions (requiring a more developed response, worth two or more marks)
If the candidates are required to provide a description of, say, three items or factors and four items or factors are provided, then mark on a
similar basis – that is downwards (as it is unlikely in this situation that a candidate will provide more than one response in each section of the
response space
...
Examiners will need to apply professional judgement as to
whether the second (or a subsequent) response is a ‘new start’ or simply a poorly expressed continuation of the first response
...


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


7
...

Team Leaders must confirm the correct use of the NR button with their markers before live marking commences and should check this
when reviewing scripts
...


The RM Assessor comments box is used by your Team Leader to explain the marking of the practice responses
...
Do not use the comments box for any other reason
...


9
...
The report should contain notes on particular strengths displayed as well as common errors or weaknesses
...


J250/07
10
...
The
indicative scientific content in the Guidance column indicates the expected parameters for candidates’ answers, but be prepared to recognise and
credit unexpected approaches where they show relevance
...


Once the level is located, award the higher or lower mark:
The higher mark should be awarded where the level descriptor has been evidenced and all aspects of the communication statement
(in italics) have been met
...

In summary:
The skills and science content determines the level
...
Level of response question on this paper is 15(b)
...


Mark Scheme

Annotations available in RM Assessor

Annotation

Meaning
Correct response
Incorrect response
Omission mark
Benefit of doubt given
Contradiction
Rounding error
Error in number of significant figures
Error carried forward
Level 1
Level 2
Level 3
Benefit of doubt not given
Noted but no credit given
Ignore

June 2024

J250/07

Mark Scheme

June 2024

Abbreviations, annotations and conventions used in the detailed Mark Scheme (to include abbreviations and subject-specific conventions)
...


Mark Scheme

June 2024

Subject-specific Marking Instructions

INTRODUCTION
Your first task as an Examiner is to become thoroughly familiar with the material on which the examination depends
...


You should ensure that you have copies of these materials
...
These are set out in the OCR
booklet Instructions for Examiners
...

Please ask for help or guidance whenever you need it
...


8

J250/07

Mark Scheme

June 2024

The breakdown of Assessment Objectives for GCSE (9-1) in Combined Science A:
Assessment Objective
AO1

Demonstrate knowledge and understanding of scientific ideas and scientific techniques and procedures
...
1

Demonstrate knowledge and understanding of scientific ideas
...
2

Demonstrate knowledge and understanding of scientific techniques and procedures
...


AO2
...


AO2
...


AO3
AO3
...

Analyse information and ideas to interpret and evaluate
...
1a

Analyse information and ideas to interpret
...
1b

Analyse information and ideas to evaluate
...
2

Analyse information and ideas to make judgements and draw conclusions
...
2a

Analyse information and ideas to make judgements
...
2b

Analyse information and ideas to draw conclusions
...
3

Analyse information and ideas to develop and improve experimental procedures
...
3a

Analyse information and ideas to develop experimental procedures
...
3b

Analyse information and ideas to improve experimental procedures
...
g
...

Question

Answer

Marks

AO
element

1

C

1

1
...
2

3

D

1

1
...
1

5

C

1

1
...
2

7

B

1

2
...
1

9

B

1

1
...
1

Guidance

J250/07

Mark Scheme

Question
11 (a)

Answer
Any two from:
Movement in both directions

Marks
2



June 2024
AO
Guidance
element
2 x 2
...
g
...
1

✓

Xylem transports mineral ions

✓

Phloem transports (dissolved) sugar

ALLOW xylem transports minerals
IGNORE just ‘ions’ / nutrients / food
DO NOT ALLOW incorrect substances e
...
sugar

✓
ALLOW sucrose for sugar / amino acids
IGNORE (dissolved) food / nutrients
DO NOT ALLOW glucose / minerals
IGNORE any reference to direction as this is
assessed in (a)

11

J250/07

Mark Scheme

Question

Answer

Marks

(c)

2
Increases (transport)

June 2024
AO
Guidance
element
2
...
1
ALLOW more evaporation from leaves

✓

ALLOW more water evaporates through the
stomata / more water vapour escapes through the
stomata

12

J250/07

Mark Scheme

Question
12 (a) (i)

Answer
Colour of (Benedict’s) solution at the end

Marks

✓

1

June 2024
AO
element
2
...
1b

Hazard must link to precaution
ALLOW do not touch / wear (heatproof) gloves
ALLOW use a water bath instead
ALLOW flame so tie hair back
ALLOW risk burning, keep Bunsen burner on
safety flame when not in use
ALLOW keep flammable objects away from
fire/flame
IGNORE hazard “Bunsen burner” / heat (needs
risk of fire / burning)
IGNORE precaution “put on heat proof mat”
IGNORE stay away from the fire / flame

Or
Liquid may spit out of tube
and wear eye protection

ALLOW safety glasses / goggles / plastic or glass
shield
IGNORE just ‘glasses’
ALLOW eye irritations from chemical / Benedict’s
and wear goggles
ALLOW point test tube away from face when
heating

✓

IGNORE references to glassware breaking

13

J250/07

Mark Scheme

Question
(b)

(i)

Answer

Marks
1

percentage concentration of
sugar in mixture

June 2024
AO
element
3
...
5 +
ALLOW ≥ 3
...
5 <

>3
...
0 - 0
...
5

(2
...
5)
1
...
5

(c)

✓

(ii)

Not a single value / range of values

(i)
(ii)

2
...
1b

1
1

2
...
3b

ALLOW idea colour change is subjective / colours
can be perceived differently / orange can be
mistaken for yellow
ALLOW it is a large interval
ALLOW values overlap

✓

Repeat (method for mixture C) and find a mean

✓

14

ALLOW repeat until they have no anomalous
values

J250/07

Mark Scheme

Question
13 (a)

Answer

Marks

First check the answer in the table
If answer = 2 : 1 award 3 marks
SA and V calculated = 54 and 27
54 ÷ 27 or 2


June 2024
AO
element

3



ALLOW correct answer written outside table but
answer in table takes precedence
1
...
2

=2:1

(b)

(i)
(ii)



523

1
1

Any one from:
Idea of difficulty in identifying when agar cube is
completely yellow

3
...
1b

ALLOW ECF from candidates’ SA and V
IGNORE any surface area, volume or ratio already
given in the table e
...
24 : 8 = 3 : 1
IGNORE any ratios that are not n : 1 e
...
8 : 3
ALLOW (agar cube) D

IGNORE student error e
...
, student recorded the
wrong time / student stopped the stop clock too
soon
IGNORE references to different concentrations of
hydrochloric acid / wrong pH / wrong volume



Idea of difficulty in cutting cubes to exact size

Guidance



IGNORE student error when measuring the cubes
IGNORE ideas that would have caused a faster
time to be obtained rather than a slower time
...
g
...
2b

Guidance
ALLOW the higher the surface area to volume
ratio the less time it took / ORA
ALLOW as the size/length/volume of the cube
increases the time taken (for the cube to turn
yellow) increases / ORA
IGNORE as the surface area increases the time
increases

ALLOW ORA
ALLOW as side gets bigger/ volume gets bigger,
the surface area to volume ratio gets smaller

As size increases the diffusion distance increases /
as ratio decreases the diffusion distance increases

ALLOW ORA
DO NOT ALLOW rate of diffusion decreases/
increases/ changes
DO NOT ALLOW references to osmosis

16

J250/07

Mark Scheme

Question
14 (a)

Answer
Receptors (in the eye) detect the stimulus

Marks



4

Impulses are sent along the neurones



June 2024
AO
Guidance
element
3 x 2
...
1

(Impulses) travel along sensory neurone to relay neurone
(in brain) to the motor neurone

(b)

(i)
(ii)

DO NOT ALLOW spinal cord / spine
DO NOT ALLOW extra steps on the pathway e
...

impulse goes from brush/stimulus to receptor



Face muscles produce the response



ALLOW muscles produce the response / effectors
produce the response
ALLOW (face) muscle contracts
ALLOW face muscle causes blinking
IGNORE just effectors



Thyroid

1
2

Any two from:

1
...
1
IGNORE increase oxygen intake



Increased heart rate

Increased blood pressure
Increased breathing rate

IGNORE messages, signals /electrical signals



Direct blood flow away from digestive system / directs



blood flow to muscles

Dilates/widens pupils / AW



Stimulates the conversion of glycogen to glucose

ALLOW increases blood glucose / blood sugar



IGNORE increased body temperature

17

J250/07

Mark Scheme

Question

Answer
Increased metabolism / increased respiration

(c)

Marks

AO
element

3

3 x 1
...
1a
2 x 2
...
1

Hormone Y / insulin converts glucose to glycogen and
glucagon converts glycogen to glucose 
Hormone Y / insulin is released when concentration of
glucose is high and glucagon is released when
concentration of glucose is low



Hormone Y / insulin lowers the concentration/level of
glucose and glucagon increases the concentration/level

ALLOW insulin lowers blood glucose and
glucagon raises blood glucose



of glucose

Hormone Y / insulin increases uptake of glucose by cells
/liver





Hormone Y / insulin increases rate of respiration

19

J250/07

Mark Scheme

Question
15 (a)

Answer

Marks

First check the answer on the answer line
If answer = 63 award 2 marks

2

June 2024
AO
element
2 x 2
...
525 x 60 x 2

=63
(b)

Please refer to the marking instructions on page 4 of this
mark scheme for guidance on how to mark this question
...
1
2 x 2
...
3a

ALLOW for one mark 32 / 31
...
05
AO2
...
The information presented is
relevant and substantiated
...
The information presented is relevant and
supported by some evidence
...
3a Analyse information and ideas to
develop investigation
• describes how to change light intensity and
states different distances
• includes repeat readings and calculates a
mean
• mention of using a heat sink / LED lamp (to
control temperature)
• use of gas syringe rather than counting
bubbles to increase accuracy
AO2
...
The information is in the most part relevant
...


21

J250/07

Mark Scheme

Question
16 (a)

Answer

Marks

Any two from:

2

Biconcave shape to increase surface area

AO
element
2 x 1
...
1

ALLOW only allows one way flow / makes sure
blood is flowing the right way
IGNORE names of valves
IGNORE controls the flow

J250/07

Mark Scheme

Question
(ii)

Answer

Marks

Only one ventricle (instead of two) / does not contain two
ventricles



Oxygenated and deoxygenated blood become mixed /
are not separated



AO
element
3 x 2

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