BIOL 202 Lecture Notes - Lecture 5: Neurospora Crassa, Mendelian Inheritance, Model Organism
Document Summary
Evidence of independent assortment: first studied in grasshopper chromosomes by carothers. The chromosomal morphology makes it easy to tell apart homologous pairs. The brown chromosomes has one long chromosome and a short chromosome heteromorphic. The purple chromosome can associate with either long brown or short brown: conclusion: independent assortment has chromosomal bases. E. g. suppose we have two homologous pairs aa/aa and bb/bb, aa can pair with. Bb or bb, therefore produce different allele combination of alleles in the gametes: recombination-new combination of alleles (from gametes of parents) other than parental type (only consider segregation at this point) *neurospora crassa (bread molds: model organism in neuroscience, dominant haploid stage. Easy to determine its genotype without worrying about dominance or recessive: transitory diploid generation after mating, 8 spores produced in a single meiosis process and one mitosis. E. g. aa aa produces aaaaaaaa (or aaaaaaaa) Polygenetic traits: traits that are quantitative, continuously varying (height weight, plant seed color)
