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COMBINED SCIENCE B

OCR 2024
GCSE Combined Science B Twenty First Century Science
J260/05: Biology (Higher Tier)

with Marking Scheme Merged
...
Do not write in the barcodes
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You can use an HB pencil, but only for graphs and diagrams
...
If you need extra space use the
lined pages at the end of this booklet
...

• Answer all the questions
...
Marks might
be given for using a correct method, even if your answer is wrong
...

• The marks for each question are shown in brackets [ ]
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• This document has 28 pages
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2
1

Charlie knows that hormones are important in human reproduction
...


...

Stage 1
Menstruation
Stage 4
Ovum dies if not fertilised

Stage 2
Uterus lining thickens
Stage 3
Ovulation

Charlie has a contraceptive implant under their skin
...

Complete the sentence to explain why the hormones released by the implant disrupt the
menstrual cycle
...

The hormones prevent stage 1 / 2 / 3 / 4 from taking place
...
The trial compared:
•
•

the risk of becoming pregnant
the risk of catching a sexually transmitted disease
...

Evaluate Charlie’s decision, using the information from the chart
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[1]

© OCR 2024

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4
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© OCR 2024

5
2

Alex has cereal for breakfast
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Which small molecule does the body get by breaking down the carbohydrate from the cereal?
Put a ring around the correct option
...

Complete the table
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Small molecule

Needed
for aerobic
respiration

Produced by
aerobic
respiration

Not needed for
or produced by
aerobic respiration

Oxygen
Urea
Water
[2]
(b) Explain how the partially-permeable cell membrane controls movement of small molecules into
and out of a cell
...


Gases such as oxygen and carbon dioxide move across the cell membrane by active transport /
diffusion / osmosis
...

Molecules can be moved against a concentration gradient using energy in a process called
active transport / diffusion / osmosis
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Which statements about how this happens are true, and which are false?
Tick (✓) one box in each row
...


Oxygen and carbon dioxide move between blood in
capillaries and air in alveoli
...

Water and food molecules are absorbed from the
digestive system into blood in capillaries
...
Alex uses cubes as models for different organisms
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Organism B represents a large organism without exchange surfaces
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2 cm

2 cm
1 cm

(i)

1 cm
1 cm

2 cm

A

B

1 cm

C

Calculate the surface area:volume ratio of organism B
...


Surface area:volume ratio =
...

Explain why the surface area:volume ratio of organism C is also 6:1
...


...

Tick (✓) one box for each row
...


(i)

Draw a scientific drawing of the chloroplast in the box
...

Explain why electron microscopy is needed to increase our understanding of sub-cellular
structures
...


...


...
In the image, the length of the chloroplast
is 65 mm
...

Use the equation: magnification =

image length
actual length

Give your answer to 2 significant figures
...
µm [4]

© OCR 2024

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10
4

Scientists study communicable diseases
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...


...
[2]

(b) HIV is a communicable disease
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HIV is a
...

HIV is transmitted in
...


(i)

Year

Number of people
living with HIV/AIDS
(millions)

Number of deaths
due to HIV/AIDS
(millions)

1990

7
...
3

1995

17
...
9

2000

25
...
6

2005

28
...
8

2010

29
...
4

2015

33
...
0

2020

37
...
9

Calculate the percentage change in the number of people living with HIV/AIDS from 1990 to
2020
...
% [2]

© OCR 2024

11
(ii) A doctor reports that people living with HIV/AIDS have had access to better medicines for
their condition over the last 20 years
...


...


...
[2]

(iii) The number of new infections with HIV has been decreasing since 1995
...


...
[1]

© OCR 2024

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13
5

Organisms need to detect and respond to changes in their internal and external environment to
survive
...

Symptoms of MS include:
•
•

slow muscle contractions in the arms and legs
unwanted muscle contractions
...

Healthy motor neuron

Motor neuron affected by MS

Explain how the structure of a motor neuron relates to its function and why MS causes the
symptoms described
...


...


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...

The graph shows the blood glucose and insulin concentration after eating a meal high
in carbohydrate
...

Give your answer to 2 decimal places
...
mg / dm / min [3]

(ii) Describe the relationship between the blood glucose and insulin concentrations between hours 6
and 7
...


...

Use ideas about insulin and glucagon in your answer
...


...


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Washing powders need to remove food stains from clothes
...


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...
[2]

(b) Trypsin is a digestive enzyme which can remove milk stains
...

A student investigates the effect of temperature on the rate of digestion of milk by
trypsin
...

Pour the trypsin into the milk
...

Repeat the test at 10 °C, 20 °C, 30 °C, 40 °C and 50 °C
...


Trypsin poured
into milk

Trypsin

(i)

Milk

Suggest one reason for repeating the test three times at each temperature
...


...

Dependant variable
...


...

1
...

2
...

[2]
(c) The milk went clear and colourless fastest at 40 °C
...
Use ideas about enzyme action in your answer
...


...


...


...

(i)

Which sub-cellular structure does aerobic respiration take place in?

...


...
[1]

© OCR 2024

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18
7

All organisms contain genetic material
...


The entire genetic material of an organism is called the
...


, which are

made of a polymer called
...


, which are

made of chains of
...


Put a ring around one nucleotide on the diagram
...

This has happened even though wild dogs separated from their wolf ancestor 18 000 years ago
...
thecommonwealth
...
Item removed due to third party copyright restrictions
...

Use ideas about natural selection in your answer
...


...


...


...

Pet dogs are a product of selective breeding
...


...


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...
[3]

© OCR 2024

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20
(e) Humans have produced 22 new breeds of dogs in the last 10 years
...

(i)

Describe what is meant by genetic engineering
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1
...

2
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3
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4
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[4]

© OCR 2024

21
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

Please turn over for the next question

© OCR 2024

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22
8
(a) The world’s human population is due to reach 10 billion by 2050
...

(i)

Explain why increasing the rate of photosynthesis would increase the amount of food available
for humans
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...

Complete the table to describe two other limiting factors and explain why increasing the amount
of each factor increases the rate of photosynthesis
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[4]

© OCR 2024

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24
9
(a) Describe two ways in which fossils have provided evidence of evolution
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(i)

The discovery was published in a scientific journal
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[2]

(ii) Some students discuss how the discovery of this dinosaur changes our understanding of the
ecosystem in which the dinosaur lived
...

The discovery of a single fossil will not tell you how abundant the species was
...

This fossil tells us exactly how the species was distributed within the ecosystem
...

When the dinosaur was alive, the new species was an abiotic component
of the ecosystem
...

Bacteria reproduce by simple cell division
...

Explain why bacteria can evolve quickly
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You must write the question numbers clearly
in the margin
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© OCR 2024

27

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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

J260/05

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

J260/05
11
...


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
...


7

J260/05

Mark scheme

June 2024

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

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

Demonstrate knowledge and understanding of scientific ideas
...
2
AO2

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
...
1

2
...
1b

contraceptive implant, risk of becoming
pregnant is lower
idea of contraceptive implant has a larger
increase of risk of catching an STD than a
decrease from getting pregnant

✓

acts as a barrier (to sperm and to pathogens)



Any named hormone must have the correct role
IGNORE ideas of puberty/secondary sexual
characteristics
ALLOW ovulation
Answer must be comparative

✓

idea larger decrease of risk of catching an STD than
increase from getting pregnant

(iii)

ALLOW any correct reference to a part of
human reproduction eg mature follicle/egg /
thicken uterus lining / produce gametes / sperm
production

ORA for contraceptive implant
contraceptive implant has more risk of catching
a sexually transmitted disease

✓

risk of becoming pregnant is higher/1% higher

Guidance

1

2
...
1
1
...


✓


Oxygen and carbon dioxide move
between blood in capillaries and air
in alveoli
...

✓
Water and food molecules are
absorbed from the digestive system into
blood in capillaries
...
1

DO NOT ALLOW more than 1 ring for each correct
statement

3

1
...
2

ALLOW ECF for correct answer to incorrect SA
substitution using numbers from the diagram




= 24(cm2)

V = 2 x 2 x 2 = 8(cm3)

(SA:V = 24:8) = 3:1



(ii)

4

idea that C is made up of lots of A

✓

1

10

2
...
1

Foun
d in
both
types
of
cells

Guidance
Four correct ticks = 3 marks
Three correct ticks = 2 marks
Two or one correct ticks = 1 mark
DO NOT ALLOW more than 1 tick for each
correct statement

✓
✓



✓✓✓
(b)

(i)

correct outline shape of this chloroplast drawn with
continuous lines and no shading

internal structures drawn accurately to scale

(ii)

2

✓

2
...


✓

Any two from:

2

electron microscopes have a high magnification

ALLOW two small errors e
...
small gap in the

1
...
7 (µm) award 4 marks
Conversion: (65 mm =) 65000 (µm)

= 5
...
7 (to 2 sig
...
)

AO
element

Guidance

4

✓
1
...
2 x 2

Rearrangement: actual length = image length /
magnification = 65000 / 11500

June 2024



✓
✓

1
...
65217391
ALLOW one mark for an incorrect answer if it is
clearly shown that it has been correctly
rounded to 2 significant figures
...
1

caused by a pathogen

✓
sexually
body fluids / semen / blood

(b)
(c)

(i)

Guidance

ALLOW example of pathogen or named
disease
...
1

2

2
...
1b

1

3
...
5 – 7
...
5) x 100
= 400 (%)

(ii)

✓

number of deaths has decreased since 2005

✓

(even though) the number of people living with HIV has



continued to increase
(iii)

Any one from:
(improved) education / awareness /public health
campaigns

✓

(more use of) condoms / safe(r) sex
use of sterile needles
improved testing

ALLOW anti-retroviral drugs, e
...
PrEP,
Truvada, PEP
DO NOT ALLOW vaccine

✓

✓

✓

13

J260/05
Question
5

(a)*

Mark scheme
Answer

Marks

Please refer to the marking instructions on page 4 of this
mark scheme for guidance on how to mark this
question
...

There is a well-developed line of reasoning which is
clear and logically structured
...

Level 2 (3–4 marks)
Gives a partial explanation of how structures of nerve
cells relate to their function
AND
Gives an explanation how MS causes the symptoms
described
There is a line of reasoning presented with some
structure
...


6

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

Guidance
AO1
...
2a Analyses information to make a
judgement on why MS causes the
symptoms described

Level 1 (1–2 marks)
Gives a partial explanation of how structures of nerve
cells relate to their function
OR
Gives an explanation how MS causes the symptoms
described
There is an attempt at a logical structure with a line of
reasoning
...

0 marks
No response or no response worthy of credit
...
2 x 2

ALLOW use of value between 77-80 (mg/dm3)
in mp1

3

3

If answer = 1
...
28333333

✓

✓

insulin concentration is low / is deceasing
AND
glucose concentration is starting to increase

1

1
...
1a

(insulin low/decreasing so) cells absorbing less glucose

2

2
...
28

(ii)

✓

ALLOW any correct rounding for mp3



(iii)

from the blood



glucagon causing liver to break down carbohydrate to
release glucose into the blood

ALLOW glycogen into glucose





15

J260/05

Mark scheme

Question
6

Answer

(a)

Marks

Any two from:
speed up / break down/digestion of (food) molecules

specific to a substrate/food molecule
(biological) catalysts
(b)

(i)

AO
element
2
...
2
ALLOW to make comparisons
ALLOW outliers

✓

✓

Independent: temperature
Dependent: time taken to go clear/colourless
Control: volume of milk/trypsin / concentration of
milk/trypsin

2

2
...
3b

IGNORE use a thermometer

✓✓

(iii)

milk/trypsin

✓

(thermostatically controlled/electric) water bath

✓

use a stop clock/watch to time low long it takes to go
colourless

✓

light meter to measure end point/colourless

ALLOW any sensible suggestion e
...
read
text/cross through milk

✓

narrower range of temperatures / small increments of
temperatures/wider range of temperatures to find
optimum temperature

ALLOW test with more temperatures

✓

start timing immediately as the trypsin is poured into the
milk as enzyme will start digestion

✓

use separate pipettes/syringe/measuring cylinder to stop
cross contamination

✓

allow time for milk/trypsin to reach desired temperature
✓

16

J260/05

Mark scheme

Question
(c)

Answer

Marks

Any three from:

3

June 2024
AO
element
2
...
1
1
...
1

1
3

3
...
1

✓

✓

✓

(dogs) with more wolf -like features more likely to eat
prey

pass on alleles/mutations/features

(i)

✓

2
...
1

✓

✓

idea of modifying genome/introduce new gene from one
organism into another

3

✓

select offspring with desired characteristics
repeat the breeding process

AW produce offspring for reproduction
ALLOW pass on advantageous allele/gene

Any three from:

breed these wolves together

✓

✓

select wolves with desired/named characteristics

(e)

ALLOW dogs are better adapted to find prey

✓

(these dogs) more likely to survive and reproduce

(d)

Guidance

✓

Any three from:
(change in phenotype) due to genetic variation / random
mutation

Marks

✓

chromosomes AND DNA

June 2024

✓

18

J260/05

Mark scheme

Question

Answer
introduce desirable characteristics

(ii)

Marks

✓

Any four from:

4

✓
isolate the gene
✓
replicate required gene
put gene into vector/plasmid

✓

use vector/plasmid to insert gene into bacteria/cell

select modified cells

✓

✓

19

June 2024
AO
element

1
...
1

ALLOW more glucose
ALLOW increase biomass for growth = 2 marks

more plants available for us /farm animals to eat /more
food produced/ more biomass produced



photosynthetic organisms/plants/producers are the
source of all food/biomass

Guidance

IGNORE producers unqualified





reference to food chains / our dependence upon plants
for food
(ii)



carbon dioxide (concentration) – (more carbon dioxide)
to react with water until not limiting

✓

2

1
...

MAX two marks for named intensive farming
practices alone or effects
MAX two marks for each pair
Credit for reducing biodiversity can only be
awarded once

✓
ALLOW description of eutrophication

monoculture

AND

2
...
1

DO NOT ALLOW the fossil record unqualified
...
g
...
1
ALLOW communicate scientific
rationale/methodology for investigations / share
ideas with other scientists / allow other
scientists to develop work/compare
data/challenge existing research
...
2a

J260/05
(c)

Mark scheme
Any two from:

2

June 2024
2
...




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