IB Biology HL C1.3.3 Oxygen As By Product Questions
Practise IB Biology HL 8.3.3 by analysing photolysis, oxygen evolution and evidence from photosynthetic organisms.
- Syllabus
- First assessment 2025
- Course
- Biology HL
- Level
- HL
Exam points
- Identify water, rather than carbon dioxide, as the source of oxygen released during photosynthesis.
- Explain that light-driven photolysis splits water and releases oxygen as a by-product, with hydrogen/electrons supporting photosynthetic reactions.
- Distinguish oxygenic photosynthesis in algae and cyanobacteria from organisms such as fungi that do not produce oxygen by this pathway.
