Human nutrition — IGCSE Science - Combined (0653) questions by topic
23 real questions make up this set, drawn from 2023 to 2025 papers and worth 1 to 10 marks, mixing single-mark labelling with multi-part explanations of enzyme denaturation. Locating the gall bladder or salivary glands on a diagram, describing physical versus chemical digestion, and explaining why a denatured enzyme stops working recur throughout, and explain in particular wants a causal link stated, not just a repeated fact.
Submitting each answer for instant marking helps confirm that a described mechanism, such as an active site changing shape at very low pH, is stated precisely rather than left vague.
What examiners look for
- A frequent confusion is writing excretion where egestion is the correct term for removing undigested waste.
- Physical digestion is often wrongly described as breaking down food molecules rather than breaking food into smaller pieces.
- The stomach should be described as very acidic, not simply acidic, since enzymes still show some activity at pH 4 to 5.
- A recurring misconception places the active site on the substrate rather than on the enzyme molecule itself.
- Strong answers describe denaturing as a molecular change caused by very low pH, and explain that the active site changes shape so the substrate no longer fits it.
May–June 2025, Paper 11
What is important for healthy teeth? A carbohydrates B fibre C iron D vitamin D
Answer this question and get it marked →May–June 2025, Paper 12
Which statement describes chemical digestion? A Food molecules pass along the alimentary canal. B Large food molecules break down into smaller molecules. C Large pieces of food…
Answer this question and get it marked →The diagram shows the alimentary canal and associated organs. Four parts are labelled P, Q, R and S. Which row shows the labels for parts P, Q, R and S? P Q R S --- --- --- ---…
Answer this question and get it marked →May–June 2025, Paper 13
What is meant by a balanced diet in humans? A a diet that contains a lot of fibre to aid food passing through the alimentary canal B a diet that has only enough of each food group…
Answer this question and get it marked →The diagram shows part of the human alimentary canal and associated organs. A large organ in the upper right of the abdomen is labelled W. What is the organ labelled W? A gall…
Answer this question and get it marked →Which row shows what happens to soluble food molecules after food is chemically digested? name of process what happens to soluble food molecules --- --- --- A ingestion pass…
Answer this question and get it marked →May–June 2025, Paper 21
What is the purpose of physical digestion? A break down food into smaller pieces B break down insoluble food into soluble molecules C change food so that it can be absorbed into…
Answer this question and get it marked →May–June 2025, Paper 22
A diet provides the correct energy requirements for a person but is not balanced. What are possible effects of this diet? 1 constipation 2 obesity 3 scurvy A 1, 2 and 3 B 1 and 2…
Answer this question and get it marked →What is a function of hydrochloric acid in the stomach? A to help absorption of all food in the stomach B to kill microorganisms in the ingested food C to prevent chemical…
Answer this question and get it marked →May–June 2025, Paper 23
A pregnant woman is told she is deficient in iron. Which food increases the iron content in her diet? A cheese B rice C milk D red meat
Answer this question and get it marked →Chemical digestion and physical digestion happen in various parts of the alimentary canal and associated organs. In which organ do both processes happen? A liver B mouth C…
Answer this question and get it marked →A test-tube is used to model the effect of protease on a protein suspension in the stomach. The diagram shows a test-tube containing protease and protein suspension at 37 °C. What…
Answer this question and get it marked →May–June 2025, Paper 41
Fats are broken down in the small intestine by chemical digestion. State the name of the enzyme that breaks down fats.
Answer this question and get it marked →May–June 2025, Paper 42
Fig. 1.1 is a diagram of the digestive system and associated organs. The diagram labels five parts with letters: A (a small organ near the top, the salivary gland region), B (the…
Answer this question and get it marked →May–June 2024, Paper 31
Fig. 1.1 is a diagram of the alimentary canal and associated organs in humans, labelled A, B, C, D, E, F. State the letter on Fig. 1.1 that identifies the position of: a salivary…
Answer this question and get it marked →May–June 2024, Paper 33
Table 7.1 shows information about some fruits (mass of nutrient per 100 g of fruit): apple — carbohydrate 13.8, protein 0.3, fat 0.2, fibre 2.4; avocado — 8.5, 2.0, 15.0, 6.7;…
Answer this question and get it marked →May–June 2024, Paper 42
Fig. 1.1 shows the alimentary canal and associated organs in humans, labelled A, B, C, D, E, F. Table 1.1 shows the name and function of some of the parts labelled in Fig. 1.1.…
Answer this question and get it marked →May–June 2024, Paper 43
Fig. 4.1 shows a model of the alimentary canal and associated organs of humans, viewed from the back, with the stomach labelled. On Fig. 4.1, draw a label line and the letter P to…
Answer this question and get it marked →October–November 2024, Paper 32
(a) Fig. 1.1 shows the alimentary canal and associated organs of a human, with structures labelled A (oesophagus), B (stomach), C (small intestine), D (liver) and E (mouth).…
Answer this question and get it marked →October–November 2024, Paper 33
(a) Fig. 1.1 shows the alimentary canal and associated organs of a human, with structures labelled A (oesophagus), B (stomach), C (small intestine), D (liver) and E (mouth).…
Answer this question and get it marked →May–June 2023, Paper 33
Fig. 4.1 is a diagram of the alimentary canal and associated organs with two unlabelled parts. Complete the labels in Fig. 4.1 with the names of the parts shown.
Answer this question and get it marked →October–November 2023, Paper 41
Fig. 1.1 shows the human alimentary canal and some associated organs, labelled A, B, C, D, E, F (with the stomach also marked). Table 1.1 shows some of the letters, names and…
Answer this question and get it marked →October–November 2023, Paper 43
Fig. 4.1 shows part of the human alimentary canal and associated organs (with the small intestine labelled). Draw a label line and the letter G on Fig. 4.1 to identify the gall…
Answer this question and get it marked →Other IGCSE Science - Combined topics
- Practical skills (96)
- Motion, forces and energy (53)
- Electricity and magnetism (38)
- Waves (32)
- Acids, bases and salts (22)
- Organisms and their environment (21)
- Organic chemistry (21)
- Reproduction (20)
- Thermal physics (20)
- Plant nutrition (19)
- The Periodic Table (18)
- Metals (18)