Genetic Variation Flashcards
(4 cards)
1
Q
Crossing over
A
Prophase 1. Portions of sister chromatids break off and reattach on homologous chromosomes. Occurs 1-3 times per chromosome. Side by side is tetrad. Overlap is chiasma.
2
Q
Independent assortment
A
Metaphase 1. Alignment of one chromosome pair doesn’t affect the alignment of any others.
3
Q
Random fertilization
A
Sperm 1:8 mill. Egg is same. Multiply, 1:64 mill chance, not counting crossing over.
4
Q
Genetic variation
A
DNA mutations and sexual reproduction
