Mendelian crosses

Mendelian crosses - genotype of the gametes. A heterozygous...

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Mendelian crosses An advantage of genetics is that scientists can predict the probability of inherited traits in offspring by  performing a genetic cross (also called a  Mendelian cross ). To predict the possibility of an individual  trait, several steps are followed. First, a symbol is designated for each allele in the gene pair. The  dominant allele is represented by a capital letter and the recessive allele by the corresponding  lowercase letter, such as  E  for free earlobes and  e  for attached earlobes. For a homozygous  dominant individual, the genotype would be  EE ; for a heterozygous individual, the genotype would  be  Ee ; and for a homozygous recessive person, the genotype would be  ee.   The next step in performing a genetic cross is determining the genotypes of the parents and the 
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Unformatted text preview: genotype of the gametes. A heterozygous male and a heterozygous female to be crossed have the genotypes of Ee and Ee . During meiosis, the allele pairs separate. A sperm cell contains either an E or an e , while the egg cell also contains either an E or an e. To continue the genetics problem, a Punnett square is used. A Punnett square is a boxed figure used to determine the probability of genotypes and phenotypes in the offspring of a genetic cross. The possible gametes produced by the female are indicated at the top of the square, while the possible gametes produced by the male are indicated at the left side of the square....
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This note was uploaded on 11/11/2011 for the course BIO 101 taught by Professor Pesthy during the Fall '07 term at Texas State.

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