Q1. [2] medium initial-understanding
What is the first step common to all pathways in which glucose is broken down for energy, and where does it occur?
Generated by claude-sonnet-4-6 · 2026-06-10 02:56 · grounding rag
Model Answer
The first step common to all pathways of glucose breakdown is glycolysis — the breakdown of glucose (6-carbon) into pyruvate (3-carbon), producing a small amount of ATP. This process occurs in the cytoplasm of the cell and takes place whether or not oxygen is available.
Source: Life Processes, Chapter 5, Respiration section
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Explanation
- The examiner expects two key facts: what the step is (glycolysis / breakdown of glucose to pyruvate) and where it occurs (cytoplasm). One mark for each.
- The phrase "common to all pathways" is the hint that glycolysis precedes both aerobic and anaerobic respiration — mention this briefly to show understanding.
- Avoid writing full equations unless asked; a crisp description earns full marks.