Respiration — IGCSE Sciences - Co-Ordinated (0973) questions by topic
Respiration questions ask how breathing rate and depth change while running, why cold weather increases food requirements in warm-blooded animals, how insects affect a sodium hydroxide-absorbed gas column, and what a milky limewater result shows for yeast and glucose, worth from 1 to 9 marks.
Identify, explain, state and calculate top the command words in this IGCSE Co-ordinated Sciences topic, with describe also common: explain an increased food requirement by linking it to maintaining body temperature, not just state the fact. 9 real questions from 2023 to 2025 papers sit here. Submitting each answer for instant marking flags a milky-limewater result mislabelled as a different gas test before it happens again.
May–June 2025, Paper 21
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…
Answer this question and get it marked →May–June 2024, Paper 21
A pupil runs to school. What happens to the rate and depth of their breathing as they run? A rate decreases, depth decreases B rate decreases, depth increases C rate increases,…
Answer this question and get it marked →May–June 2024, Paper 22
A student places a mixture of yeast and glucose in a boiling tube, covers it with a layer of oil, and uses a delivery tube to bubble gas through limewater. After 10 minutes, the…
Answer this question and get it marked →May–June 2023, Paper 12
During cold weather, warm blooded animals, such as mammals and birds, require more food. Which statement explains the reason for this? A energy required to maintain constant body…
Answer this question and get it marked →May–June 2023, Paper 21
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…
Answer this question and get it marked →May–June 2023, Paper 22
During cold weather, warm blooded animals, such as mammals and birds, require more food. Which statement explains the reason for this? A energy required to maintain constant body…
Answer this question and get it marked →October–November 2023, Paper 11
The apparatus shown is set up and left for 10 minutes. The insects move around in the test-tube but the wire mesh prevents them falling into the sodium hydroxide (which absorbs…
Answer this question and get it marked →October–November 2023, Paper 21
Aerobic respiration releases energy from nutrient molecules. One molecule of glucose requires ...(1)... molecules of oxygen. The reaction releases ...(2)... molecules of carbon…
Answer this question and get it marked →October–November 2023, Paper 41
A student investigates the effect of different types of sugar on anaerobic respiration in yeast. She mixes yeast with five different sugar solutions of the same concentration and…
Answer this question and get it marked →Other IGCSE Sciences - Co-Ordinated topics
- Motion, forces and energy (77)
- Electricity and magnetism (65)
- Practical skills (60)
- Organic chemistry (40)
- Waves (40)
- Atoms, elements and compounds (29)
- Organisms and their environment (28)
- Stoichiometry (24)
- Chemical reactions (22)
- The Periodic Table (22)
- Human nutrition (21)
- Reproduction (21)