1. Year 10, Pathway C
2012
New Generations

2. Variation
Variation is the differences between the characteristics found within a species
Variation is beneficial as it increases diversity within a species which can help it adapt to changes in the environment.

3. Examples of Variation

4. Causes of Variation Variation is caused by meiosis
During DNA replication each chromosome pair may swap some of their genes with each other. This only occurs between two chromosomes in the same pair.
Chromosome pairs contain the same information (ie: eye colour, hair colour). But the instruction may be different (blue eyes or brown eyes).
Every daughter cell in meiosis ends up with one chromosome from each pair. So one daughter cell may have instruction for blue eyes, while another has brown eyes.

5. Variation in a family Mum Dad Zygote
Because of the crossover during meiosis, even individuals within a family are different from each other.