A heterozygous blue-nose pit bull breeds with another blue nosed pit bull. Their
litter contains 2 puppies with black noses. What are the genotypes of the parents?

Bb and bb

Explanation:

one parent might be a carrier of the black-nose gene and the other parent is not OR both parents can be carriers of the black-nose gene.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.

the answer is cell division : )