BIOL 100 Lecture Notes - Lecture 13: Human Skin Color, Gene Expression, Punnett Square
Document Summary
Distinguish between the law of segregation and law of independent assortment. Use a punnett square to determine the genotypes and phenotypes of offspring. Cross between two heterozygous parents is a monohybrid cross. If both gametes have dominant alleles, offspring will have two dominant alleles (homozygous dominant) One gamete has dominant and the other has recessive allele= offspring will be heterozygous. Law of independent assortment: separation of alleles for one gene does not influence the separation of alleles for another gene, each person has a pair of genes for any trait and passes on randomly to offspring. Can be used to find relative proportion of offspring phenotypes and genotypes. Only linked if they occur on same chromosome. Inheriting one allele influences the likelihood of inheriting a linked allele. Gene expression does not always follow simple dominant and recessive pattern. Do(cid:373)i(cid:374)a(cid:374)t allele does(cid:374) t co(cid:373)pletely block phenotypes of recessive allele. More than one allele encodes functional protein.
