ANTHR-140 Lecture Notes - Lecture 27: Red Blood Cell, Mutation Rate, Point Mutation

• School: Diablo Valley College
• Department: Anthropology
• Course: ANTHR-140
• Professor: mercer

Document Summary

Explanation of gaps in the fossil record. Polymorphism: the situation in a species or population where there are 2 or more alleles of a gene, and at least 2 of the alleles have a frequencies greater than or equal to 1 percent. The mutation rate for any gene is very low, so it cannot get an allele up to 1%, so something else has to be acting on the allele to reach the threshold of 1%. Polymorphism is explained by natural selection acting on mutations. In our species, approximately 28% of our genes are polymorphic. Let"s say there are 50,000 genes in our genome and 28% are polymorphic. This means there are approximately 14,000 polymorphic genes. Genetic variability allows a species to go through natural selection and adapt. Example: a, b, o blood system: the genotypes are aa, a0, ab, bb, The proteins that can be produced are a,a, a and b, b, b, and none for the oo.