Respiration — Paper 2 · IGCSE Sciences - Co-ordinated (Double) 0654

3 Aerobic respiration is summarised below. glucose + oxygen → carbon dioxide + water How many molecules of carbon dioxide will be produced from the breakdown of four molecules of glucose? A 4 B 8 C 16 D 24

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2017

3 Four test-tubes were set up as shown in the diagram. Which test-tube will contain the most dissolved oxygen after 24 hours? A B C D water pond aquatic snail plant light light dark dark

1 marks

Answer: A

This question in 0654/21 Oct/Nov 2018

6 Which word equation for anaerobic respiration in yeast is correct? A glucose → carbon dioxide + alcohol B glucose → carbon dioxide + water C glucose → lactic acid + alcohol D glucose → lactic acid + water

1 marks

Answer: A

This question in 0654/21 Oct/Nov 2018

12 The diagram shows part of the carbon cycle. Which arrow represents plant respiration? carbon compounds A in the air B carbon compounds carbon compounds in plants C in rocks, sea and soil D carbon compounds in animals

1 marks

Answer: B

This question in 0654/21 Oct/Nov 2018

6 What is meant by respiration? A breakdown of protein B sweating to lose heat C the function of lungs D the release of energy

1 marks

Answer: D

This question in 0654/22 Oct/Nov 2018

7 What is the equation for aerobic respiration? A 6CO2 + 6H2O → C6H12O6 + 6O2 B 6CO2 + C6H12O6 → 6O2 + 6H2O C 6O2 + 6H2O → C6H12O6 + 6CO2 D 6O2 + C6H12O6 → 6CO2 + 6H2O

1 marks

Answer: D

This question in 0654/22 Oct/Nov 2018

1 One way to test for microscopic life in soil is to see if carbon dioxide is released. Which characteristic of living things is being tested? A growth B nutrition C reproduction D respiration

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2018

13 The diagram shows part of the carbon cycle. Which arrow represents plant respiration? carbon compounds A in the air B carbon compounds carbon compounds in plants C in rocks, sea and soil D carbon compounds in animals

1 marks

Answer: B

This question in 0654/23 Oct/Nov 2018

8 After sprinting 200 metres as fast as possible, an athlete could not continue and was breathing deeply. What had accumulated in her muscles? A alcohol B carbon dioxide C lactic acid D water

1 marks

Answer: C

This question in 0654/22 May/June 2019

8 Hydrogencarbonate indicator changes colour with different concentrations of carbon dioxide. less more carbon dioxide carbon dioxide purple red yellow A pond contains both plants and animals. Samples of pond water are taken during a sunny day and again during the night. Each sample is tested with hydrogencarbonate indicator. What would be the results of these tests? day sample night sample A purple yellow B red purple C red red D yellow purple

1 marks

Answer: A

This question in 0654/23 May/June 2019

8 What are the products of the anaerobic respiration of glucose in yeast? A alcohol and carbon dioxide B alcohol only C lactic acid and carbon dioxide D lactic acid only

1 marks

Answer: A

This question in 0654/21 Oct/Nov 2019

8 What are the products of the anaerobic respiration of glucose in yeast? A alcohol and carbon dioxide B alcohol only C lactic acid and carbon dioxide D lactic acid only

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2019

8 What are the products of the anaerobic respiration of glucose in yeast? A alcohol and carbon dioxide B alcohol only C lactic acid and carbon dioxide D lactic acid only

1 marks

Answer: A

This question in 0654/23 Oct/Nov 2019

1 Which characteristic of living organisms is defined as the chemical reactions that break down nutrient molecules and release energy for metabolism? A excretion B nutrition C respiration D reproduction

1 marks

Answer: C

This question in 0654/21 May/June 2020

10 An experiment using germinating seeds is set up as shown, and left at room temperature for 12 hours. to pump solution P solution Q germinating damp peas cotton wool The pump is then switched on and air is drawn through the apparatus for 2 minutes. Which row identifies solutions P and Q and the results obtained? solution P solution P results solution Q solution Q results A ethanol remains colourless ethanol turns milky B ethanol turns milky limewater remains colourless C limewater remains colourless limewater turns milky D limewater turns milky ethanol remains colourless

1 marks

Answer: C

This question in 0654/21 May/June 2020

8 Which row shows the products of anaerobic respiration in yeast cells? lactic acid CO, alcohol A v x x B x Jv J Cc x x J D Jv Jv x

1 marks

Answer: B

This question in 0654/23 May/June 2020

8 What is the word equation for anaerobic respiration in yeast? A glucose  alcohol + carbon dioxide B glucose  carbon dioxide + water C glucose  lactic acid D glucose + oxygen  carbon dioxide + water

1 marks

Answer: A

This question in 0654/21 Oct/Nov 2020

1 What is respiration? A breakdown of food by enzymes in the alimentary canal B breathing to supply oxygen to cells C release of carbon dioxide from the lungs D release of energy for body activities

1 marks

Answer: D

This question in 0654/21 May/June 2021

1 What is respiration? A breakdown of food by enzymes in the alimentary canal B breathing to supply oxygen to cells C release of carbon dioxide from the lungs D release of energy for body activities

1 marks

Answer: D

This question in 0654/22 May/June 2021

1 What is respiration? A breakdown of food by enzymes in the alimentary canal B breathing to supply oxygen to cells C release of carbon dioxide from the lungs D release of energy for body activities

1 marks

Answer: D

This question in 0654/23 May/June 2021

13 The diagram shows a simplified carbon cycle. Which labelled arrow represents respiration? CO2 B C A green D animals plants fossil fuels

1 marks

Answer: C

This question in 0654/21 Oct/Nov 2021

1 Which processes do green plants carry out? 1 detect stimuli and make appropriate responses 2 break down nutrient molecules to release energy for metabolism 3 take in carbon dioxide, water and ions for energy, growth and development A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

1 marks

Answer: D

This question in 0654/22 Oct/Nov 2021

13 The diagram shows a simplified carbon cycle. Which labelled arrow represents respiration? CO2 B C A green D animals plants fossil fuels

1 marks

Answer: C

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

13 The diagram shows a simplified carbon cycle. Which labelled arrow represents respiration? CO2 B C A green D animals plants fossil fuels

1 marks

Answer: C

This question in 0654/23 Oct/Nov 2021

13 When fertiliser is washed into lakes, it leads to changes in the oxygen concentration and the population of algae. algae oxygen time Which statement explains the change in oxygen over time? A The algae use up the oxygen for photosynthesis. B Decomposer bacteria use up the oxygen for respiration. C Nitrates react with the oxygen. D The algae use up the oxygen for respiration.

1 marks

Answer: B

This question in 0654/22 May/June 2022

8 What is the relative concentration of glucose, lactic acid and oxygen in the muscles immediately after extreme exercise? glucose lactic acid oxygen A high high low B high low high C low high low D low low high

1 marks

Answer: C

This question in 0654/23 May/June 2022

8 Which diagram gives the possible products of aerobic respiration and anaerobic respiration? A B aerobic anaerobic aerobic anaerobic lactic H2O H2O acid lactic alcohol acid CO2 CO2 alcohol C D aerobic anaerobic aerobic anaerobic lactic lactic acid acid CO2 H2O H2O CO2 alcohol alcohol

1 marks

Answer: D

This question in 0654/21 Oct/Nov 2022

8 Which diagram of a cell shows the correct movement of substances for the process of aerobic respiration? A B glucose oxygen glucose oxygen carbon water carbon water dioxide dioxide C D glucose oxygen glucose oxygen carbon water carbon water dioxide dioxide

1 marks

Answer: C

This question in 0654/22 Oct/Nov 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

8 What is the word equation for anaerobic respiration in yeast? A glucose  alcohol + carbon dioxide B glucose  carbon dioxide + water C glucose  lactic acid D glucose + oxygen  carbon dioxide + water

1 marks

Answer: A

This question in 0654/22 Feb/March 2023

1 What is meant by respiration? A protein synthesis B sweating to lose heat C the function of lungs D the release of energy

1 marks

Answer: D

This question in 0654/21 May/June 2023

8 Which statement about anaerobic respiration is correct? A It does not cause an oxygen debt. B It occurs in the muscles during vigorous exercise. C It uses oxygen to release energy from nutrient molecules. D It releases more energy per glucose molecule compared to aerobic respiration.

1 marks

Answer: B

This question in 0654/21 May/June 2023

8 During cold weather, warm blooded animals, such as mammals and birds, require more food. Which statement explains the reason for this? energy required to rate of maintain constant respiration body temperature A high high B high low C low high D low low

1 marks

Answer: A

This question in 0654/22 May/June 2023

8 Endothermic reactions use up more energy than they release while exothermic reactions release energy overall. Which row describes the type of reaction that occurs in the process of photosynthesis and in the process of respiration? respiration photosynthesis A endothermic endothermic B endothermic exothermic C exothermic endothermic D exothermic exothermic

1 marks

Answer: C

This question in 0654/23 May/June 2023

1 Which characteristic of a living organism releases energy for growth? A excretion B reproduction C respiration D sensitivity

1 marks

Answer: C

This question in 0654/21 Oct/Nov 2023

8 Aerobic respiration releases energy from nutrient molecules. One molecule of glucose requires … 1 … molecules of oxygen. The reaction releases … 2 … molecules of carbon dioxide and … 3 … molecules of water. Which row completes gaps 1, 2 and 3? 1 2 3 A six two two B two six six C two two two D six six six

1 marks

Answer: D

This question in 0654/21 Oct/Nov 2023

8 An experiment is set up, as shown. level X boiling tube coloured liquid live insects wire mesh soda lime (absorbs carbon dioxide) What will happen to the level of coloured liquid at X? A It goes down. B It goes up. C It goes up and then down. D It stays the same.

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2023

8 Which substances are used and produced in aerobic respiration? carbon dioxide oxygen glucose water A produced used produced used B produced used used produced C used produced produced used D used produced used produced

1 marks

Answer: B

This question in 0654/22 Feb/March 2024

1 Which processes are done by green plants? 1 detect stimuli and make appropriate responses 2 break down nutrient molecules to release energy for metabolism 3 take in carbon dioxide, water and ions for energy, growth and development A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

1 marks

Answer: A

This question in 0654/21 May/June 2024

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

8 A student places a mixture of yeast and glucose in a boiling tube, as shown in the diagram. They cover the mixture with a layer of oil. A delivery tube is used to bubble gas produced by the yeast through limewater. After 10 minutes, the limewater is milky. screw clip (closed when experiment is started) oil yeast and glucose limewater solution Why does the limewater go milky? A The yeast produces carbon dioxide by anaerobic respiration. B The yeast produces lactic acid by anaerobic respiration. C The yeast produces carbon dioxide by photosynthesis. D The yeast produces oxygen by aerobic respiration.

1 marks

Answer: A

This question in 0654/22 May/June 2024

8 Which process releases the most energy? A carbon dioxide + water  glucose + oxygen B glucose + oxygen  carbon dioxide + water C glucose  alcohol + carbon dioxide D glucose  lactic acid

1 marks

Answer: B

This question in 0654/23 May/June 2024

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

1 marks

Answer: B

This question in 0654/21 Oct/Nov 2024

8 Which equation shows the metabolic process used in bread making? A carbon dioxide + water  glucose + oxygen B glucose + oxygen  carbon dioxide + water C glucose  ethanol + carbon dioxide D glucose  lactic acid

1 marks

Answer: C

This question in 0654/23 Oct/Nov 2024

7 An athlete runs as fast as possible. After 200 m, the athlete cannot continue and is breathing deeply. What accumulated in the athlete’s muscles? A alcohol B carbon dioxide C lactic acid D water

1 marks

Answer: C

This question in 0654/22 Feb/March 2025

8 Yogurt is a food made by adding bacteria to milk. The bacteria feed on sugars in the milk and produce lactic acid. The lactic acid denatures the milk protein. Which process produces the lactic acid? A aerobic respiration B anaerobic respiration C assimilation D decomposition

1 marks

Answer: B

This question in 0654/21 May/June 2025

9 Two flasks are set up as shown. A student breathes out through tube X of flask 1. Another student breathes in through tube Y of flask 2. flask 1 flask 2 X Y limewater limewater The students obtain different results. Which body process causes this difference? A absorption B assimilation C digestion D respiration

1 marks

Answer: D

This question in 0654/21 Oct/Nov 2025

9 The word equation for aerobic respiration is shown. glucose + oxygen  carbon dioxide + water How many molecules of carbon dioxide will be produced from the breakdown of four molecules of glucose? A 4 B 8 C 16 D 24

1 marks

Answer: D

This question in 0654/22 Oct/Nov 2025

6 Scientists measure the heart rate of an athlete during and after exercise. Which point on the graph shows the time when the oxygen debt is removed from the athlete? A B heart rate C D time exercise ends

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2025