AQA GCSE Combined Science: Trilogy Biology Paper 1 (Foundation), 2023: Question 4
13 marks · Standard Demand difficulty · Short Answer
Identify heart structures and blood vessel types, explain capillary adaptations, interpret blood component data from a table, and explain how increased red blood cell count benefits athletes.
Practise this questionQuestion
Question text
04 Figure 6 shows a human heart.
Figure 6
04.1 The vena cava carries blood into the heart from the body.
Which blood vessel in Figure 6 is the vena cava?
[1 mark]
Tick ( ) one box.
A B 19C D
04.2 Which chamber of the heart pumps blood to the body?
[1 mark]
Tick ( ) one box.
Left atrium
Left ventricle
Right atrium
Right ventricle
04.3 What is the name of the blood vessel that carries blood to the heart muscle?
[1 mark]
Tick ( ) one box.
Aorta
Coronary artery
Pulmonary artery 20
The heart and some blood vessels contain valves.
04.4 Which type of blood vessel has valves?
[1 mark]
Tick ( ) one box.
Artery
Capillary
Vein
04.5 What is the function of valves?
[1 mark]
Figure 7 shows a blood capillary.
Figure 7
04.6 Explain one way the capillary is adapted for its function.
[2 marks]
Table 2 shows information about the blood of four people.
Table 2
Concentration of blood component in number/mm3
Person
Red blood cells White blood cells Platelets
W 5 000 000 15 000 200 000
X 4 700 000 5 500 20 000
Y 8 000 000 7 200 250 000
Z 4 900 000 6 400 225 000
04.7 Person W has 5 000 000 red blood cells in 1 mm3 of blood.
*21* What is 5 000 000 written in standard form?
[1 mark]
Tick ( ) one box.
5 × 1 000 000
5 × 106
5 × 107
50 × 105
04.8 Draw one line from each description to the person in Table 2 it describes.
[2 marks]
Description Person in Table 2
Person W
Person most likely to have an infection
Person X
Person whose blood will not clot properly
Person Y
24 Person Z
04.9 The greater the height above sea level, the less oxygen there is in the air.
People who live high above sea level have more red blood cells than people who live
at sea level.
Some athletes train in mountains high above sea level.
Explain why having more red blood cells will improve an athlete’s performance.
[3 marks]
Mark scheme
Show the mark scheme
Question 4
AO /
Question Answers Extra information Mark
Spec. Ref.
04.1 A 1 AO1
4.2.2.2
AO /
Spec. Ref.
04.2 left ventricle 1 AO1
4.2.2.2
AO /
Spec. Ref.
04.3 coronary artery 1 AO1
4.2.2.2
4.2.2.4
AO /
Spec. Ref.
04.4 vein 1 AO1
4.2.2.2
AO /
Spec. Ref.
04.5 to stop blood flowing in the allow to stop blood flowing 1 AO1
wrong direction backwards 4.2.2.2
allow to stop backflow (of blood)
allow to keep blood flowing in
the correct direction
AO /
Spec. Ref.
04.6 walls that are one cell thick allow thin walls 1 AO1
ignore thin unqualified 4.2.2.2
do not accept references to cell
walls
(so) there is a short diffusion allow (so) substances can move 1
distance (quickly) between blood and
cells / tissues
allow (so) diffusion / movement
can happen faster
allow (so) there is a short
distance for substances to move
OR
large surface area (to volume
ratio) (1)
for exchange of substances (1) allow (so) more substances can
diffuse / move at the same time
(1)
allow (very) narrow (1)
(so) are close to cells (1)
AO /
Spec. Ref.
04.7 5 × 106 1 AO2
4.2.2.3
AO /
Question Answers Mark
Spec. Ref.
04.8 AO3
4.2.2.3
do not accept more than one line from a box on the left
AO /
Spec. Ref.
04.9 more oxygen (can be allow red blood cells carry 1 AO2
transported / carried) oxygen 4.2.2.3
4.4.2.1
(oxygen) is needed for (aerobic) allow (so) less anaerobic 1 4.4.2.2
respiration respiration
(so) more energy can be do not accept energy is made / 1
transferred / released produced / created
Total Question 4 13
How to answer it
The Human Heart, Blood Vessels, and Blood
This question assesses your knowledge of heart anatomy, the structure and function of blood vessels (arteries, veins, and capillaries), the components of blood, and how to interpret biological data using standard form.
Heart Anatomy & Blood Supply
Correct Answers
- 04.1: A (Vena Cava)
- 04.2: Left Ventricle
- 04.3: Coronary Artery
Key Knowledge
- Vena Cava: Carries deoxygenated blood from the body to the right atrium.
- Left Ventricle: Has the thickest muscular wall because it must pump blood at high pressure to the entire body.
- Coronary Arteries: These supply the heart muscle itself with glucose and oxygen for respiration.
🧠 Exam Technique: Labeling the Heart
Remember that diagrams are shown as if you are looking at a person facing you. This means the Left side of the heart is on the Right side of the paper. Always double-check your "Lefts" and "Rights"!
Valves and Blood Vessels
Correct Answers
- 04.4: Vein
- 04.5: To prevent the backflow of blood (or to keep blood flowing in the correct direction).
🧠 Examiner Insight
For the function of valves, use the specific term "backflow". While "stopping blood going the wrong way" is often accepted, "preventing backflow" is the professional scientific term that guarantees the mark.
Capillary Adaptations
Explain one way the capillary is adapted for its function.
Model Answer (2 Marks)
The capillary walls are one cell thick [1 mark] which provides a short diffusion distance for substances like oxygen and glucose [1 mark] .
❌ Common Error: "Thin Cell Walls"
Do not say capillaries have "thin cell walls". Plant cells have cell walls; animal cells do not. You must say the vessel wall is one cell thick. Examiners will often reject "thin walls" if it isn't qualified by "one cell thick".
Blood Components & Data
📐 Calculation: Standard Form (04.7)
Convert 5,000,000 into standard form:
- Place the decimal after the first non-zero digit: 5.0
- Count how many places the decimal moved from the end: 6 places.
- Answer: 5 × 10⁶
04.8 Matching Answers
- Infection: Person W (Highest White Blood Cell count: 15,000).
- Not clotting: Person X (Lowest Platelet count: 20,000).
Key Knowledge
- White Blood Cells: Part of the immune system; numbers increase to fight pathogens.
- Platelets: Small fragments of cells that trigger blood clotting at wound sites.
Performance & Respiration
Explain why more red blood cells improve an athlete's performance.
Model Answer (3 Marks)
- More red blood cells means more oxygen can be transported to the muscles. [1 mark]
- This allows for more aerobic respiration. [1 mark]
- Therefore, more energy is released for muscle contraction. [1 mark]
❌ The "Energy" Trap
Never say energy is "made", "produced", or "created". Energy is released or transferred. Using the word "made" can lose you the mark in many biology mark schemes.
🧠 Linking Concepts
Top-level answers always link the biological feature (RBCs) to the chemical process (Respiration) and then to the outcome (Energy release). If you miss any step in this chain, you will likely lose marks.
Topics
Biology · B2: Organisation · B4: Bioenergetics
Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Biology Paper 1 (Foundation), 2023. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.