2.2.4—Photosynthesis
- Syllabus
- First assessment 2026
- Objective
- 2.2.4
- Level
- SL
Photosynthesis uses light energy to transform carbon dioxide and water into glucose, oxygen and stored chemical energy.
CO₂ and water supply the atoms; light supplies energy. Glucose can become starch, cellulose, lipids and other biomass.
A leaf uses light to build glucose from CO₂ and water; that glucose later becomes cellulose in a growing stem.
No. Matter comes from CO₂ and water; light provides the energy to rearrange it.
Light is an energy input, not the atoms in plant biomass.