# 2 - o dP= p’-p = 0 = no evolution • AA=p^2 Aa=2pq...

This preview shows page 1. Sign up to view the full content.

How to get streptomycin resistant gene, how does mutation appear? o Millions of different mutations occur, and only one of them will happen, by chance, to be the  resistance to strepto.  Size at time t = 2^t if population doubles every hour (without strep) If it doubles every two hours, then St= 2^ t/2 (with strep) Rt= 2^t (resistant bacteria doubling time)  Rt/St = 2^t/2 (exponential function)  2n= 46 chromatids for people or 23 pairs of chromosomes Locus: location on chromosome (or two loci) Mutation at locus that gets transferred to another chromosome = variant Variation at locus = alleles P’= p prime = frequency of p= p^2 + ½ pq / total (p^2+2pq+a^2)=1 o P’= p^2+pq= p(p+q) so p’=p (no evolution, alleles are same every generation
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: o dP= p’-p = 0 = no evolution • AA=p^2 Aa=2pq aa=q^2 • Nutrasweet o Di-peptide Phenylalamine (sp) + aspartic acid => PKU (Phenoketonurics can’t process phe) Phe (when in excess) => (by hydroxylase) tyrosine (in normal body) (Phe accumulates but can be broken down) In PKU body, phen => (by hydroxylase) tyrosine • However, Phen accumulates in body & is toxic Phenoketonurics damages phehydroxolate => accumulation PHe that can’t be broken down Those with recessive alleles don’t have enzyme to digest phe. (PKUs) • Dd= 2pq = 2(1-10^-2)10^-2 = 1/50 = .0198 • DD = p^2 == (1-10^-2) = .98 • Evolution (no agent p’=p and dP = 0) which is hardy weinberg o Selection o Migration o Mutation o Drift o other...
View Full Document

## This note was uploaded on 02/05/2012 for the course BIEB 150 taught by Professor Chao during the Winter '11 term at San Diego.

Ask a homework question - tutors are online