Variation (Leaving Cert Biology): Revision Notes
📚 Revision Notes
Variation
infoNote
Variation means that there are differences between the members of a species.
- Evolution cannot occur without variation.
- The two causes of variation are:
- Sexual reproduction
- Mutations
- Sexual reproduction causes variation through meiosis (crossing over and random assortment of chromosomes) and fertilisation, which combines genetic material from two parents.
- A mutation is a change in the amount or structure of DNA.