BIOSC-116 Lecture Notes - Lecture 32: Morgan Morgan, Chromosome, Stoma
26 Aug 2020
School
Department
Course
Professor
Document Summary
Hereditary information is on genes and genes are located on chromosomes. Egg and sperm contribute equally to the genetic endowment of offspring through their nuclei. The inheritance of genes corresponds to the inheritance of chromosomes. Thomas hunt morgan: experimented with drosophila, found a gene determining eye color resides on the x chromosome. Found a mutant white-eyed male amongst thousands of wild-type red eyed flies: traced its inheritance. Morgan seen a white eyed male fly and traced its genes. Took a homozygous wild-type red eyed female and bred it with a hemizygous mutant white eyed male. He thought red was the dominant allele; so bred f1 offspring together. Morgan did not get the 3:1 ratio. Found the 3:1 ratio in the f2 progeny. But only kept getting white eyed males; no white eyed. Suspected the gene is on the x chromosome. Got homozygous white eyed female from heterozygous red. Did a reciprocal cross females eyed female with white eyed male.
