IGCSE Biology glossary
Glucose
Biology editorial review is supported by the named review panel. Reviewer participation may vary by guide. Checked against Cambridge IGCSE Biology 0610 (2026–2028); last reviewed August 2026.
Definition
A simple sugar (monosaccharide) with the formula C6H12O6 that serves as the primary substrate for respiration in cells. It is produced during photosynthesis and digestion of carbohydrates, and is transported in the blood to supply energy.
What to include in an exam answer
In respiration equations, always use glucose as the substrate. In photosynthesis, glucose is the product. Know both the word equation and the balanced symbol equation involving glucose.
Example in context
State what happens to glucose during aerobic respiration (2 marks): Glucose is broken down using oxygen to release energy, producing carbon dioxide and water.
Related syllabus topic
Biological molecules