Genetic variation is advantageous because it enables some individuals and, therefore, a population, to survive despite a changing environment.
Answer:
1/3 of black F2 progeny will be homozygous.
Explanation:
Here, BB = black coat color = true breeding dominant black strain
bb = white coat color = true breeding recessive white strain
When true breeding black and white guinea pigs are mated to give F1 progeny:
BB X bb = Bb ( all black guinea pigs )
When two of the F1 guinea pigs are mated to give F2 progeny:
Bb X Bb = BB, Bb, Bb, bb
F2 progeny has 3/4 progeny as black (BB and Bb) . Out of them 1/3 are homozygous and 2/3 are heterozygous.
Hence, 1/3 of black F2 progeny will be homozygous.
-it transports nutrients in the body
-it circulates macrophage in the body
