LIFESCI 4 Lecture Notes - Lecture 2: Dihybrid Cross, Phenotype, Heredity
Document Summary
Mendel"s conclusions: from these experiments mendel reached the following explanations for the data. Gene determinant of heredity that affects certain characteristics (flower color) Allele separate form of a gene (purple vs. white) Each individual has 2 copies of each gene. Each sex cell has 1 copy of each gene. Either of the two alleles goes with equal frequency into sex cell (and progeny) Sex cell union is random: mendel"s model explains data. Phenotype physical traits: mendel"s 1st law: law of segregation. Factors exist in pairs in each organism. One parent transmits one member of a pair to an offspring; therefore they segregate . A progeny gets one factor from its mother and one factor from its father and thus has a pair of factors: testing mendel"s hypothesis. Test cross (backcross) test cross always to homozygous recessive to figure out genotype: mendel"s 2nd law: law of independent assortment. Allele pairs separate independently during the formation of the gametes.
