An organism shows the dominant phenotype, then one of its genes has to be the dominant allele,
but you cannot be sure of the identity of the other allele
unless you do a test cross to see if the dominant parent
breeds pure. let's pretend that you are in the dog-breeding
business. you know that long hair on a “pooch hound” is a
dominant allele and short hair is recessive. you purchase
a male long-haired "pooch hound." how do you figure out if your
male “pooch hound” is homozygous or heterozygous for long hair?
which genotype of female should you breed him to?
if a proper test cross is used, what phenotypes of puppies would you see
if your male dog is heterozygous dominant?
what puppy phenotypes would you see if your male dog is homozygous
dominant?
- complete the punnett square to
show the test cross that would convince someone that your "pooch hound"
is homozygous for long hair.
male genotype: -
female genotype: