Cambridge Notes
O Level
Biology

O Level Biology Notes (5090)

Cambridge O Level Biology (5090) revision notes by topic — syllabus-aligned key concepts and revision for CAIE exam preparation.

1. Cells

1.1 Cell structure and function
1.2 Specialised cells tissues and organs
1.3 Features of organisms

2. Classification

2.1 Concept and use of a classification system
2.2 Features of organisms

3. Movement into and out of cells

3.1 Diffusion and osmosis
3.2 Active transport
3.3 Active transport

4. Biological molecules

4.1 Biological molecules

5. Enzymes

5.1 Enzyme action
5.2 Effects of temperature and pH

6. Plant nutrition

6.1 Photosynthesis
6.2 Leaf structure
6.3 Mineral nutrition

7. Transport in flowering plants

7.1 Uptake and transport of water and ions
7.2 Transpiration and translocation
7.3 Physical digestion
7.4 Chemical digestion
7.5 Absorption 1

8. Human nutrition

8.1 Xylem and phloem
8.2 Water uptake
8.3 Transpiration
8.4 Translocation

9. Human gas exchange

9.1 Human gas exchange
9.2 Heart
9.3 Blood vessels
9.4 Blood

10. Respiration

10.1 Respiration
10.2 Aerobic respiration
10.3 Anaerobic respiration

11. Transport in humans

11.1 Circulatory system
11.2 Heart
11.3 Blood vessels
11.4 Blood

12. Disease and immunity

12.1 Disease
12.3 Anaerobic respiration

13. Excretion

13.1 Excretion
13.2 Urinary system

14. Coordination and control

14.1 Mammalian nervous system
14.2 Mammalian sense organs
14.3 Hormones
14.4 Homeostasis
14.5 Temperature control
14.6 Blood glucose control

15. Coordination and response in plants

15.1 Coordination and response in plants

16. Development of organisms and continuity of life

16.1 Nuclear division
16.2 Asexual and sexual reproduction
16.3 Sexual reproduction in plants
16.4 Sexual reproduction in humans
16.5 Sex hormones in humans
16.6 Sexually transmitted infections

17. Inheritance

17.1 Chromosomes genes and proteins
17.3 Inheritance
17.4 Monohybrid inheritance

18. Biotechnology and genetic modification

18.1 Biotechnology
18.2 Genetic modification
18.3 Selection

19. Relationships of organisms with one another and with the environment

19.1 Energy flow
19.2 Nutrient cycles
19.3 Ecosystems and biodiversity
19.4 Effects of humans on ecosystems
19.5 Conservation