Reproduction

What this lesson covers

Reproduction is a 7-part O Level Biology lesson. Each part makes one point and then hands over to the next, so it can be read in a sitting or picked up again at the part you stopped on. It defines the idea in plain words before using it, works through an example step by step, breaks the topic into its parts and compares them, names the mistakes that cost marks in an exam, ends with a recap of what to remember.

How it begins

Asexual reproduction involves one parent and no gametes, and produces offspring that are genetically identical to the parent, clones. Advantages: fast, no mate needed, useful traits preserved exactly. Disadvantage: no genetic variation, so the whole population is vulnerable to the same disease or environmental change.

The 7 parts

1. The two kinds of reproduction, and their trade-off
2. Flowers: pollination and fertilisation
3. The human reproductive system and the gametes
4. The menstrual cycle and pregnancy
5. Where marks go
6. What to remember
7. Watch one worked through