8.1 origins of genetic variation Flashcards
1
Q
what three processes are sources of genetic variation?
A
- meiosis
- mutation
- random fertilisation
2
Q
what are the two ways meiosis brings about genetic variation?
A
- independant assortment
- crossing over
3
Q
what is independant assortment?
A
when chromosome pairs from the mother and father are distributed into gametes randomly
4
Q
what is crossing over?
A
an exchange of genetic material between chromosomes at a chiasma to make recombianants
5
Q
what are the two types of mutation that bring about genetic variation?
A
- point mutations
- chromosomal mutations
6
Q
how does random fertilisation bring about genetic variation?
A
- lots of sperm
- several ova start to mature at the start of the month and it just depends which one reaches ovulation first
