AQA GCSE Biology Biology Paper 1 (Foundation), June 2023: Question 6

13 marks · Standard Demand difficulty · Short Answer

Answer questions on plant tissues, drug discovery from plants, calculating chemical yield from diseased leaves, and the purpose of clinical trials and peer review.

Practise this question

Question

Question text

06 A root is a plant organ.

Plant roots contain many different types of tissue.

06.1 What is a tissue?

[1 mark]

06.2 Tissue in the tip of a plant root contains stem cells.

Stem cells can differentiate into any type of cell.

Name the type of tissue in plants that contains stem cells.

[1 mark]

In the past many drugs were extracted from plants.

06.3 Aspirin is a painkiller.

Which plant does aspirin originate from?

[1 mark]

Scientists have extracted chemical A from the deadly nightshade plant.

Chemical A can be used as a painkiller.

Table 5 shows information about where chemical A is found.

Table 5

Part of deadly Mass of chemical A in 100 g of

nightshade plant plant tissue in grams

Roots 1.3

Leaves 1.2

Berries 0.7

06.4 The scientists usually extract chemical A from the berries of the deadly

nightshade plant.

Suggest one reason why berries are used instead of leaves or roots.

[1 mark]

A deadly nightshade plant has chlorosis (yellow leaves).

The mass of chemical A found in the leaves of the plant is 60% of the mass shown

in Table 5.

06.5 Calculate the mass of chemical A in 200 g of the leaves with chlorosis.

Give your answer in mg.

[4 marks]

Mass of chemical A = mg

06.6 Suggest one reason why the leaves of the deadly nightshade plant have chlorosis.

[1 mark]

Chemical A has not been tested in large-scale clinical trials in the UK.

06.7 It is important for drugs to be tested in clinical trials before the drugs are approved for

use by the public.

Give two reasons why.

[2 marks]

There are many online reports making claims about the effects of chemical A.

Some of these reports are biased.

06.8 Suggest one reason why a report making claims about the effects of chemical A may

be biased.

[1 mark]

06.9 How can scientists be sure that claims about new drugs are valid?

[1 mark]

Tick ( ) one box.

Advertise the claims on social media.

Ask an international company to produce the drug.

Have the claims peer reviewed.

Publish the claims in a newspaper.

Mark scheme

Show the mark scheme

Question 6

AO /

Question Answers Extra information Mark

Spec Ref.

06.1 a group of the same / similar ignore a group of cells 1 AO1

cells unqualified 4.2.1

a group of cells with a (similar / ignore examples of tissue

specific) function functions

AO /

Spec Ref.

06.2 meristem (tissue) 1 AO1

4.1.1.4

4.1.2.3

4.2.3.1

AO /

Spec Ref.

06.3 willow ignore named parts of willow 1 AO1

4.3.1.9

AO /

Spec Ref.

06.4 any one from: 1 AO3

4.2.3.1

• (berries are) easy to access / ignore berries are not

pick underground

• easier to extract chemical

• taking berries will not harm allow taking leaves / roots might

the plant damage / kill the plant (so it

cannot produce more chemical)

allow idea that the lower mass /

amount (of chemical) will be less

toxic / harmful

allow greater mass of berries

than of leaves / roots

AO /

Spec Ref.

allow conversion to mg at any

06.5 AO2

point in calculation

4.3.3.1

(0.6 × 1.2 =) 0.72 1

(0.72 × 2 =) 1.44 1 21

1.44 × 1000 allow conversion of a correct 1

mass calculated for berries /

roots

1440 (mg) allow a correct answer using an 1

incorrect conversion factor of a

multiple of 10

alternative route

(2 × 1.2 =) 2.4 (1)

(2.4 × 0.6 =) 1.44 (1)

1.44 × 1000 (1)

1440 (mg) (1)

AO /

Spec Ref.

06.6 any one from: 1 AO1

allow lack of chloroplasts 4.3.3.1

• lack of chlorophyll

4.3.1.2

4.3.1.4

• lack of magnesium (ions) allow lack of mineral (ions) or

named example such as iron /

nitrate / potassium / zinc (ions)

ignore lack of nutrients /

nitrogen

allow lack of water

allow incorrect pH of soil

allow acidic / alkaline soil

allow (named) infection

allow lack of light

allow other correct suggestions

AO /

Spec Ref.

06.7 any two from: 2 AO1

22 4.3.1.9

• to check toxicity allow to check it is safe

allow to check for side effects

allow to check it is not

poisonous / dangerous / harmful

• to check dosage allow to check how much is

needed

• to check its efficacy allow to check it works

allow to check it does not

interact with other drugs

AO /

Spec Ref.

06.8 (writers / companies may get) 1 AO3

financial gain 4.3.1.9

(competitor may suffer) financial

loss

ignore because the report has

not been peer reviewed

ignore have not used a double-

blind trial

AO /

Spec Ref.

06.9 have the claims peer reviewed 1 AO1

4.3.1.9

Total Question 1 13

How to answer it

Plant Biology, Deficiency Diseases & Drug Development

What this question tests

This question evaluates your foundational knowledge of plant organisation and practical applications in medicine. Specifically, it assesses:

Cell organisation: Defining a tissue and naming plant stem cell tissue (meristems).
Origins of medicines: Recalling that aspirin originates from willow bark.
Quantitative reasoning: Extracting tabular data, calculating percentages, scaling quantities, and converting units ( g to mg ).
Plant pathology: Understanding mineral deficiency causing chlorosis (magnesium ions / chlorophyll).
Clinical trials: Recalling the main aims of testing (toxicity, efficacy, dose) and scientific integrity (bias and peer review).

Question 06.1 • 1 Mark

Definition of a Tissue

What is a tissue?

✅ Acceptable Answers (Any one)

A group of the same or similar cells.
A group of cells with a specific (or similar) function.

❌ Common Errors & Pitfalls

Writing just "a group of cells" without qualifying that they are similar or work together for a specific function.
Listing examples of tissues (e.g. xylem, phloem) rather than defining what a tissue is.

Mark scheme tip: Standard GCSE definition: Cells → Tissues → Organs → Organ Systems. Always include either similar structure or shared function.

Question 06.2 • 1 Mark

Plant Stem Cells

Name the type of tissue in plants that contains stem cells.

✅ Correct Answer

Meristem (or meristem tissue)

💡 Key Knowledge

Meristems are found at growing tips of roots and shoots. Unlike animal stem cells, plant meristem cells can differentiate into any type of plant cell throughout the plant's life.

Question 06.3 • 1 Mark

Origins of Medicines: Aspirin

Which plant does aspirin originate from?

✅ Correct Answer

Willow (or willow tree / willow bark)

💡 Classic Drug Origins to Memorise

Aspirin: Willow tree
Digitalis (heart drug): Foxgloves
Penicillin (antibiotic): Penicillium mould

Question 06.4 • 1 Mark

Experimental Method & Harvesting

Suggest one reason why berries are used instead of leaves or roots.

✅ Acceptable Answers (Any one)

Picking berries does not damage or kill the plant (taking roots kills it; stripping leaves stops photosynthesis).
Berries are easier to access or pick (roots are buried underground).
It is easier to extract the chemical from soft berries.
Lower concentration in berries means the extracted mass may be less toxic to handle.

🧠 Exam Technique

Table 5 shows berries have less chemical A (0.7 g) than roots (1.3 g) or leaves (1.2 g). Therefore, the reason cannot be "berries contain more chemical". Think about practical farming/harvesting and plant survival!

Question 06.5 • 4 Marks

Quantitative Calculation: Yield & Chlorosis

Calculate the mass of chemical A in 200 g of the leaves with chlorosis. Give your answer in mg.

📐 Step-by-Step Calculation

Given Data:

Normal leaves: 1.2 g of chemical A per 100 g of tissue.
Chlorotic leaves have only 60% of the chemical found in normal leaves.
Target tissue mass: 200 g . Final unit required: mg .

Step 1: Calculate the mass for chlorotic leaves per 100 g
1.2 g × 0.60 = 0.72 g [1 mark]

Step 2: Scale from 100 g to 200 g of tissue
0.72 g × 2 = 1.44 g [1 mark]

Step 3: Convert grams to milligrams (1 g = 1000 mg)
1.44 g × 1000 = 1440 mg [1 mark for ×1000, 1 mark for correct answer]

Alternative Method:
1. Find normal chemical mass in 200 g: 1.2 × 2 = 2.4 g
2. Apply 60%: 2.4 × 0.60 = 1.44 g
3. Convert: 1.44 × 1000 = 1440 mg

Final Answer: 1440 mg

❌ Common Errors That Lose Marks

Unit Traps: Leaving the answer as 1.44 (forgot to convert to mg) or dividing by 1000 ( 0.00144 ).
Wrong Row in Table: Using values for roots ( 1.3 g ) or berries ( 0.7 g ) instead of leaves ( 1.2 g ).
Forgetting Sample Mass: Calculating for 100 g ( 720 mg ) and forgetting to double for the 200 g sample.

Question 06.6 • 1 Mark

Plant Disease: Chlorosis

Suggest one reason why the leaves of the deadly nightshade plant have chlorosis.

✅ Acceptable Answers (Any one)

Lack of magnesium (ions)
Lack of chlorophyll / lack of chloroplasts
Lack of light
Lack of iron ions
Infection by a pathogen (e.g. tobacco mosaic virus)

❌ What the Examiner Ignores

"Lack of nutrients" or "lack of minerals" — this is far too vague! You must name a specific ion: magnesium.
"Lack of nitrogen" alone is not the primary cause credited for yellowing in this context (nitrate deficiency causes stunted growth).

Question 06.7 • 2 Marks

Clinical Trials: Core Purpose

Give two reasons why it is important for drugs to be tested in clinical trials before approval.

✅ Three Core Pillars (Give any two)

Toxicity: To check if the drug is safe / not poisonous / has harmful side effects.
Dosage: To determine the optimum dose (the most effective amount with minimal side effects).
Efficacy: To test whether the drug actually works (cures or relieves symptoms).

🧠 Exam Technique: The "3 T's & E's" Rule

Always remember the three criteria of drug testing: Toxicity, Efficacy, Dose. Whenever asked "Why test drugs?", writing any two of these guarantees 2/2 marks.

Questions 06.8 & 06.9 • 2 Marks

Scientific Bias & Peer Review

06.8 • 1 Mark

Why might a report be biased?

Financial gain / commercial interest (e.g. company wants to sell the drug to make money, or competitor wants it to fail).

Do NOT write: "Not peer reviewed" or "didn't use double-blind trials". These affect reliability/validity, not the personal motive/bias of the author.

06.9 • 1 Mark

How can scientists be sure claims are valid?

◻ Advertise the claims on social media.
◻ Ask an international company to produce the drug.
☑ Have the claims peer reviewed.
◻ Publish the claims in a newspaper.

Peer review involves other independent scientists checking the methodology and findings before publication to prevent false claims.

Topics

Biology · B1: Cell Biology · B2: Organisation · B3: Infection and Response

Question and mark scheme from the AQA GCSE Biology examination, Biology Paper 1 (Foundation), June 2023. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.