Science question : What does a woman have two of that a cow has four of?

How does the study of genetic disorders such as pku biologists understand normal alleles?

What are the two main phases of a cell cycle

In a cross between individuals of a species of tropical fish, all of the male offspring have long tail fins, and none of the females possess the trait. mating two of the f1 fish fails to produce females with the trait. explain the inheritance pattern of the trait.