Gas exchange in humans — Paper 2 · IGCSE Sciences - Co-ordinated (Double) 0654

2 What is the order of decreasing diameter of the structures found in the breathing system? A alveoli → bronchi → capillaries B alveoli → capillaries → bronchi C bronchi → alveoli → capillaries D capillaries → bronchi → alveoli

1 marks

Answer: C

This question in 0654/21 May/June 2017

2 What is an effect of tar on the gas exchange system? A paralysis of the cilia B speeds up the build-up of cholesterol C stimulates the production of adrenaline D stops oxygen combining with haemoglobin

1 marks

Answer: A

This question in 0654/22 May/June 2017

5 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 0654/21 Oct/Nov 2017

7 What is an effect of carbon monoxide on the gas exchange system? A It causes lung cancer. B It causes the alveoli to stick together. C It slows down the diffusion of carbon dioxide through the alveoli. D It stops oxygen from combining with haemoglobin.

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2018

8 During vigorous exercise there is an increase in the rate of breathing. What causes the increase in the rate of breathing? A a decrease in the adrenaline concentration in the blood B a decrease in the lactic acid concentration in the blood C an increase in the alcohol concentration in the blood D an increase in the carbon dioxide concentration in the blood

1 marks

Answer: D

This question in 0654/21 May/June 2019

8 Cigarette smoke paralyses the cilia in the gas exchange system. What is the direct result of this? A Mucus accumulates in the airways. B Oxygen cannot diffuse into the blood. C The blood cannot carry oxygen efficiently. D The smoker develops lung cancer.

1 marks

Answer: A

This question in 0654/21 May/June 2020

8 Which cells produce mucus in the human breathing system? A alveoli cells B capillary cells C ciliated cells D goblet cells

1 marks

Answer: D

This question in 0654/22 May/June 2020

5 Which part of a leaf is involved in opening and closing the stomata during gas exchange? A chloroplast B guard cell C palisade mesophyll D phloem

1 marks

Answer: B

This question in 0654/23 May/June 2020

8 Which row is correct for inspired air and expired air? inspired air / % expired air / % oxygen carbon dioxide oxygen carbon dioxide A 17 4 17 4 B 17 4 21 0.04 C 21 0.04 17 4 D 21 0.04 21 0.04

1 marks

Answer: C

This question in 0654/22 Oct/Nov 2020

8 A student breathed gently in and out of the mouth piece of the apparatus shown. mouth piece tube limewater P Q What were the results after 10 breaths? P Q A clear clear B clear milky C milky clear D milky milky

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2020

8 When a person was walking or running, the following measurements were taken. speed number of volume of each / km per hour breaths per minute breath / dm3 4 16 1 6 18 2 8 20 3 How many dm3 of air did the person breathe per minute when running at 6 km per hour? A 18 B 36 C 60 D 108

1 marks

Answer: B

This question in 0654/22 Feb/March 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 0654/21 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 0654/22 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 0654/23 May/June 2021

8 Which diagram shows the rate and depth of breathing of a person before and during exercise? A B before during before during C D before during before during

1 marks

Answer: B

This question in 0654/21 Oct/Nov 2021

8 The graph shows the changes in volume of air in the lungs at rest and during exercise. 6 exercise 5 4 rest volume of air in 3 lungs / dm3 2 1 0 time What was the effect of exercise on the rate and depth of breathing? rate of breathing depth of breathing A decrease decrease B decrease increase C increase decrease D increase increase

1 marks

Answer: D

This question in 0654/22 Oct/Nov 2021

8 A person ran up as many stairs as they could in one minute. What would be the effect on their breathing? depth of breathing rate of breathing A decreased decreased B decreased increased C increased decreased D increased increased

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2021

8 The diagram shows the main structures in the breathing system of humans. S R P Q Which row identifies the larynx, bronchus, trachea and bronchioles? larynx bronchus trachea bronchioles A P Q R S B R P S Q C S P R Q D S Q P R

1 marks

Answer: C

This question in 0654/22 Feb/March 2022

8 An athlete is running 1000 m. Which graph shows the changes in their breathing rate and the concentration of carbon dioxide in their vena cava during the run? A B breathing rate breathing rate CO2 concentration CO2 concentration in the vena cava in the vena cava time time start end start end of run of run of run of run C D breathing breathing rate rate CO2 concentration in the vena cava CO2 concentration in the vena cava time time start end start end of run of run of run of run

1 marks

Answer: C

This question in 0654/23 Oct/Nov 2022

5 The diagram shows a cross-section through a leaf. Which tissue is adapted for gas exchange? A B C D

1 marks

Answer: D

This question in 0654/21 Oct/Nov 2023

8 What is the expected concentration of oxygen and the water vapour content in expired air? oxygen / % water vapour A 16 saturated B 16 variable C 21 saturated D 21 variable

1 marks

Answer: A

This question in 0654/23 Oct/Nov 2023

8 A pupil runs to school. What happens to the rate and depth of their breathing as they run? rate depth A decreases decreases B decreases increases C increases decreases D increases increases

1 marks

Answer: D

This question in 0654/21 May/June 2024

2 The diagram shows some cells in the gas exchange system. Which label shows the part of the gas exchange system where these cells are found? A B D C

1 marks

Answer: B

This question in 0654/21 Oct/Nov 2024

8 Changes in the body occur as a result of increased physical activity. increased increased effect effect physical respiration R S activity in cells What are effects R and S? effect R effect S A decrease in blood carbon dioxide decrease in breathing rate B decrease in blood lactic acid increase in breathing rate C increase in blood carbon dioxide increase in breathing rate D increase in blood lactic acid decrease in breathing rate

1 marks

Answer: C

This question in 0654/22 Oct/Nov 2024

13 During physical activity, the rate and depth of breathing increases. This increase in breathing is caused by the detection of an increase in carbon dioxide concentration. Which row describes this detection? location where organ that increase is detects the detected increase A alveoli brain B alveoli lungs C blood brain D blood lungs

1 marks

Answer: C

This question in 0654/23 May/June 2025

6 The diagram shows a section through a leaf. Which labelled part enables oxygen to escape from the leaf? D A C B

1 marks

Answer: C

This question in 0654/21 Oct/Nov 2025

8 The diagram shows part of the breathing system in humans. Which labelled part is the trachea? A B D C

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2025