Attempt this full Biology paper under exam conditions, then mark yourself using the answers provided.
Section A — Objective
Answer: C. Photosynthesis is only carried out by green plants, not all living things. Respiration, excretion and nutrition are universal.
Answer: C. The nucleus controls cell activities because it contains the genetic material (DNA).
Answer: A. Water leaves the cell by osmosis, so the cell becomes flaccid (and may undergo plasmolysis).
Answer: B. Photosynthesis uses carbon dioxide and water (with sunlight and chlorophyll) to make glucose and oxygen.
Answer: C. The alveoli are tiny air sacs with thin walls where oxygen and carbon dioxide are exchanged.
Answer: A. Arteries carry blood away from the heart (except the pulmonary artery which carries deoxygenated blood to the lungs).
Section B — Theory
Model answer:
1. Aerobic uses oxygen; anaerobic does not.
2. Aerobic releases much energy; anaerobic releases little energy.
3. Aerobic produces CO₂ and water; anaerobic produces lactic acid (animals) or ethanol and CO₂ (yeast).
4. Aerobic occurs in mitochondria; anaerobic occurs in the cytoplasm.
Model answer: Distilled water is a dilute (hypotonic) solution. Water enters the red blood cell by osmosis because the cell’s contents are more concentrated. The cell swells and eventually bursts — a process called haemolysis — because it has no cell wall.
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