LIFESCI 15 Lecture Notes - Lecture 5: Gregor Mendel, Master Sergeant, Karyotype
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A trait can change over time within a species if : variation for a trait, heritability, differential reproductive success. Feb 1865: gregor mendel spoke on inheritance in pea plants . Karyotype: a picture of all the chromosomes in a cell. On a homologous pair, at every locus is the same gene. A gamete receives only 1 allele for each gene (even though the organism generally has 2) The law of segregation points out that a gamete receives only one allele from the pair of alleles possessed by an organism. The allele you pass on for one trait has no effect on which allele you pass on for some other trait. (independent assortment) We see a dominant-trait phenotype: b__ = bb or bb. What cross would help? x homozygous recessive bb (the test cross) The test cross allows you to determine whether individuals showing the dominant trait are homozygous or heterozygous. Harry"s father had tons of hair, even at age 90.
