Plant nutrition — IGCSE Science - Combined (0653) questions by topic
Testing leaves for starch, tracking chlorophyll's role in photosynthesis, and reading bubble-count rate data are the recurring demands: explaining why a covered leaf area stays unstained by iodine, and linking gas-bubble counts to the rate of photosynthesis under changing light. Explain, identify and state lead the command words, and explain wants the light and chlorophyll link stated together, not separately.
This set has 19 real questions from 2023 to 2025 papers, worth 1 to 11 marks, so a single test result sits beside a full explanation of a de-starching experiment. Submitting each answer for instant marking helps confirm that light and chlorophyll are both linked explicitly to the iodine result, rather than only one factor being mentioned.
What examiners look for
- Reports note that candidates often identify light and chlorophyll as the relevant factors but do not link the results in the question to the explanation.
- The strongest answers connect both factors directly to the blue-black iodine colour seen only where the leaf was green and lit.
- Where a leaf area is no longer green, examiners credit answers that predict the corresponding colour change with iodine testing.
May–June 2025, Paper 11
The diagrams show four identical, well-watered plants in different environments. Each apparatus initially contains atmospheric air. Which plant will produce the most oxygen? A…
Answer this question and get it marked →Which part of a leaf of a dicotyledonous plant contains chloroplasts? A cuticle B palisade mesophyll C phloem D stomata
Answer this question and get it marked →May–June 2025, Paper 12
A student labels a section through a leaf as shown. The labels are A upper epidermis, B palisade mesophyll, C spongy mesophyll and D stomata. Which label is not correct? A upper…
Answer this question and get it marked →May–June 2025, Paper 13
Which substance is required for photosynthesis to occur? A chlorophyll B glucose C haemoglobin D oxygen
Answer this question and get it marked →May–June 2025, Paper 21
The diagrams show four root hair cells. Each cell is surrounded by soil with the same volume of water present. Which root hair cell absorbs water the most rapidly? A a root hair…
Answer this question and get it marked →What is the balanced equation for photosynthesis? A CO2 + H2O → C6H12O6 + O2 B CO2 + 6H2O → 6C6H12O6 + O2 C 6CO2 + 6H2O → C6H12O6 + 6O2 D 6CO2 + 12H2O → 6C6H12O6 + 6O2
Answer this question and get it marked →The diagram shows a transverse section through a leaf, with four labelled layers: layer 1 (waxy cuticle on the upper surface), layer 2 (upper epidermis), layer 3 (palisade…
Answer this question and get it marked →May–June 2025, Paper 22
Four tubes that contain red hydrogencarbonate indicator are set up as shown. After five hours, the colour of the hydrogencarbonate indicator is recorded. Tube 1: aquatic plant in…
Answer this question and get it marked →May–June 2025, Paper 23
An aquatic plant is in a test-tube of water. The test-tube is sealed and placed in the dark. The diagram shows a sealed test-tube containing water with an aquatic plant submerged…
Answer this question and get it marked →May–June 2025, Paper 32
Fig. 2.1 is a diagram of a cross-section through a leaf. The upper part shows a row of tall, closely packed rectangular palisade mesophyll cells containing many chloroplasts;…
Answer this question and get it marked →May–June 2025, Paper 43
Fig. 2.1 is a diagram of a cross-section through a leaf. The diagram shows, from top to bottom: a thin outer layer over the top (G) and the upper epidermis (F); a row of tall,…
Answer this question and get it marked →May–June 2024, Paper 63
A student investigates the growth of plants. Procedure: step 1 measures the mass of three potted plants A, B and C; step 2 gives each plant 50 cm³ of different concentrations of…
Answer this question and get it marked →October–November 2024, Paper 32
Plants manufacture carbohydrates by the process of photosynthesis. The carbohydrates are then stored as starch in the leaves. (a) Three plants of the same type, A, B and C, are…
Answer this question and get it marked →October–November 2024, Paper 33
Plants manufacture carbohydrates by the process of photosynthesis. The carbohydrates are then stored as starch in the leaves. (a) Three plants of the same type, A, B and C, are…
Answer this question and get it marked →October–November 2024, Paper 43
(a) The photosynthesis reaction in plants is controlled by enzymes. (a)(i) The rate of photosynthesis in a submerged aquatic plant is measured by counting the number of gas…
Answer this question and get it marked →May–June 2023, Paper 31
The leaves of some plants have green and white areas; only the green areas of the leaf contain chlorophyll. Fig. 7.1 shows a green and white leaf. Glucose from photosynthesis is…
Answer this question and get it marked →May–June 2023, Paper 32
A student investigates photosynthesis: adds indicator solution to three test-tubes A, B and C; puts one leaf into B and one into C; puts a bung into each; wraps test-tube C with…
Answer this question and get it marked →May–June 2023, Paper 41
Two young potted plants are left to grow in a room with no light: plant A placed upright, plant B placed on its side. Fig. 7.1 shows the plants after 10 days (pale yellow leaves;…
Answer this question and get it marked →October–November 2023, Paper 63
A student investigates the effect of light on a plant with variegated leaves (green parts with chlorophyll, white parts without). The plant is de-starched in the dark, a strip of…
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)
- Human nutrition (23)
- Acids, bases and salts (22)
- Organisms and their environment (21)
- Organic chemistry (21)
- Reproduction (20)
- Thermal physics (20)
- The Periodic Table (18)
- Metals (18)