AQA GCSE Combined Science: Trilogy Biology Paper 1 (Foundation), 2022: Question 3

9 marks · Standard Demand difficulty · Short Answer

Identify pathogens for rose black spot, TMV, and malaria, and explain the impact of leaf discoloration on plant growth and methods of disease control.

Practise this question

Question

A multi-part GCSE biology question about diseases. It includes multiple-choice questions on the pathogen types for rose black spot and TMV, short-answer questions on the effects of yellow leaves on plant growth, a matching task for controlling rose black spot, and questions on the transmission and prevention of malaria.
Question text

03 This question is about disease.

Rose black spot is a disease where black spots develop on the leaves of rose plants.

03.1 What type of pathogen causes rose black spot disease?

[1 mark]

Tick ( ) one box.

Bacterium

Fungus

Protist

Virus

03.2 Plants with rose black spot disease often have yellow leaves.

Suggest one reason why the leaves are yellow instead of green.

[1 mark]

03.3 Explain why plants with yellow leaves grow slowly.

[2 marks]

03.4 The spread of rose black spot can be controlled using different methods.

Draw one line from each method of control to the explanation of how it works.

[2 marks]

Method of control Explanation

Creates a barrier to the

movement of pathogens

Remove and burn

infected leaves

Pathogens are killed

Reduces the chance of

pathogens being spread

by water droplets

Water the roots of

the plant only, not the

leaves

Reduces the temperature

so pathogens reproduce

less

03.5 Tobacco plants may become infected with a pathogen called TMV.

What type of pathogen is TMV?

[1 mark]

Tick ( ) one box.

Bacterium

Fungus

Protist

Virus

Malaria is a disease caused by a protist.

03.6 How is the malaria pathogen transferred to humans?

[1 mark]

03.7 How can the spread of malaria pathogens be reduced?

[1 mark]

Tick ( ) one box.

Avoid sexual contact

Cook food thoroughly

Drain water from swamps

Use a tissue when sneezing

Mark scheme

Show the mark scheme The mark scheme for question 3, totaling 9 marks. It specifies 'fungus' for rose black spot, 'less chlorophyll' for yellow leaves, and links slow growth to reduced photosynthesis and glucose production. It also shows the correct matching for control methods and identifies TMV as a virus, malaria transmission via mosquitoes, and prevention by draining swamps.

Question 3

AO /

Question Answers Extra information Mark

Spec. Ref.

03.1 fungus 1 AO1

4.3.1.4

AO /

Spec. Ref.

03.2 less / no chlorophyll allow reference to chloroplasts 1 AO2

or for chlorophyll 4.4.1.2

chlorophyll has been broken

down

AO /

Spec. Ref.

03.3 less photosynthesis 1 AO2

or 4.3.1.4

less light absorbed 4.4.1.1

4.4.1.2

(so) less glucose / sugar formed 1

or

less light absorbed (1)

(so) less photosynthesis (1)– OMBINED SCIENCE: TRILOGY – –

AO /

Spec. Ref.

03.4 AO2

4.3.1.4

extra line from a box negates that box

AO /

Spec. Ref.

03.5 virus 1 AO1

4.3.1.2

AO /

Spec. Ref.

03.6 by mosquito bites allow by mosquitos 1 AO1

– OMBINED SCIENCE: TRILOGY – – 4.3.1.5

AO /

Spec. Ref.

03.7 drain water from swamps 1 AO2

4.3.1.5

Total Question 3 9

How to answer it

Plant Diseases and Malaria

What this question tests

This question assesses your ability to identify different types of pathogens (fungi, viruses, protists), explain how disease affects plant growth via photosynthesis, and identify methods to control the spread of infection in both plants and humans.

Part (a) - Question 03.1 & 03.5

Identifying Pathogens

Correct Answers

  • 03.1: Fungus (Rose Black Spot)
  • 03.5: Virus (TMV - Tobacco Mosaic Virus)

Key Knowledge

You must memorise the specific pathogen for each disease in the AQA spec:

  • Fungi: Rose black spot
  • Virus: TMV, HIV, Measles
  • Bacteria: Salmonella, Gonorrhoea
  • Protist: Malaria
Part (b) - Question 03.2 & 03.3

Disease and Plant Growth

Linking symptoms to biological processes

Correct Answers

03.2: The leaves are yellow because there is less chlorophyll (or chlorophyll has been broken down).

03.3: (2 Marks)
1. There is less photosynthesis (or less light absorbed).
2. Therefore, less glucose/sugar is produced for growth.

Exam Technique

When asked to explain slow growth in plants, always use this logical chain:

Yellow leaves → Less Chlorophyll → Less Light absorbed → Less Photosynthesis → Less Glucose → Less Growth.

Common Errors

Students often say "the plant can't get enough food." In Biology, plants make their own food (glucose). You must mention photosynthesis or glucose specifically to get the marks.

Part (c) - Question 03.4

Controlling Plant Disease

Correct Matching

  • Remove and burn leaves → Pathogens are killed.
  • Water roots only → Reduces the chance of pathogens being spread by water droplets.

Examiner Tip

The question asks for one line from each method. If you draw two lines from one box, the examiner will mark it as incorrect even if one of the lines is right. Be precise!

Part (d) - Question 03.6 & 03.7

Malaria Transmission

Correct Answers

03.6: By mosquito bites (or just "by mosquitoes").

03.7: Drain water from swamps.

Key Knowledge

Mosquitoes are vectors. They carry the protist from one person to another without getting sick themselves. Draining swamps works because mosquitoes breed in standing water; no water means fewer mosquitoes, which means less spread.

Common Errors

Do not confuse preventing the disease with treating it. "Using a tissue" or "cooking food" are for respiratory or digestive diseases, not malaria.

Total Marks Available: 9 Marks

Topics

Biology · B3: Infection and Response · B4: Bioenergetics

Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Biology Paper 1 (Foundation), 2022. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.