Gas exchange in humans — Paper 1 · IGCSE Sciences - Co-ordinated (9-1) 0973

8 As a molecule of carbon dioxide is removed from the body, in which order does it pass through these structures? A pulmonary artery → capillary → alveolus → bronchiole B pulmonary artery → capillary → bronchiole → alveolus C pulmonary vein → capillary → alveolus → bronchiole D pulmonary vein → capillary → bronchiole → alveolus

1 marks

Answer: A

This question in 0973/11 May/June 2020

8 A child blows into a rubber balloon. What is the percentage of oxygen inside the balloon? A 0% B 4% C 16% D 21%

1 marks

Answer: C

This question in 0973/11 May/June 2021

2 Which diagram correctly shows the diffusion of carbon dioxide and oxygen between an alveolus and a capillary? A B air entering air entering blood blood flow flow blood blood flow flow key carbon dioxide oxygen C D air entering air entering blood blood flow flow blood blood flow flow

1 marks

Answer: C

This question in 0973/12 May/June 2021

8 A child blows into a rubber balloon. What is the percentage of oxygen inside the balloon? A 0% B 4% C 16% D 21%

1 marks

Answer: C

This question in 0973/12 May/June 2021

8 When a person exercises for 10 minutes, what is the effect on the depth and rate of their breathing? depth of breathing rate of breathing A decreases decreases B decreases increases C increases decreases D increases increases

1 marks

Answer: D

This question in 0973/12 May/June 2022

8 In the diagram of the human breathing system, which structures are correctly labelled? trachea bronchiole bronchus alveoli A alveoli and bronchiole B alveoli and trachea C bronchus and bronchiole D bronchus and trachea

1 marks

Answer: B

This question in 0973/11 May/June 2023

8 A person inflates a balloon by breathing into it. What is the composition of the air in the balloon? percentage of percentage of oxygen carbon dioxide A 0.04 21 B 4 16 C 16 4 D 21 0.04

1 marks

Answer: C

This question in 0973/11 May/June 2024

2 By which process does oxygen pass from the alveoli to the blood capillaries in the lungs? A diffusion B osmosis C secretion D transpiration

1 marks

Answer: A

This question in 0973/12 May/June 2024

8 Which statement about the composition of expired air, compared with inspired air, is correct? A The percentage of carbon dioxide is decreased and the percentage of water vapour is increased. B The percentage of carbon dioxide is increased and the percentage of water vapour is increased. C The percentage of oxygen is decreased and the percentage of carbon dioxide is decreased. D The percentage of oxygen is increased and the percentage of carbon dioxide is decreased.

1 marks

Answer: B

This question in 0973/12 May/June 2024

10 The diagram shows the human gas exchange system. Which label shows the diaphragm? D A B C

1 marks

Answer: C

This question in 0973/11 May/June 2025

9 Which row shows the percentages for inspired air and expired air? inspired air / % expired air / % oxygen carbon dioxide oxygen carbon dioxide A 21 0.04 17 4 B 21 0.04 21 0.04 C 17 4 17 4 D 17 4 21 0.04

1 marks

Answer: A

This question in 0973/12 May/June 2025

2 The diagram shows part of the breathing system in humans. X Which cell type makes up part of structure X? A ciliated B gamete C palisade mesophyll D phloem

1 marks

Answer: A

This question in 0973/11 Oct/Nov 2025

10 Which gas in expired air has a greater percentage composition than in inspired air? A carbon dioxide B methane C nitrogen D oxygen

1 marks

Answer: A

This question in 0973/11 Oct/Nov 2025