ECON 1BB3 Lecture Notes - Endosperm, Gamete, Polyploid

• School: McMaster University
• Department: Economics
• Course: ECON 1BB3
• Professor: Hannah Holmes

Document Summary

-generation time (longer and longer generation times has an effect on mutation rate) The number of cell divisions that occur prior to gamete formation affects the number of mutations. Typical sperm undergo 25 divisions until zygotes are formed (for fruit flies) -- but 400 divisions for humans. We wary of what we"re comparing for mutation rates. Mutations generally considered on the basis of quantity of point mutations. Bio 3ff3 page 2 chromosome inversion - mechanism. Inversions affect gene order and, therefore, alignment during prophase i, preventing cross-overs, so contained alleles are inherited as a unit. These units commonly are transmitted like alleles and change frequencies in geographic manner, forming clines chromosome inversion - frequencies. If natural selection can operate on a gene in favour, it can also act on a collection of inversion genes. Often tend to be inherited a as a single unit. The first arrival of drosphila in s. a. was in 1970s and n. a.