Question

Which of these principles/laws explains why the F1 of a monohybrid or dihybrid cross all have the same phenotype?.

a. Equal segregation

b. Dominance

c. Uniformity

d. Independent Assortment.

Answer 1

There is no law in genitics called equal segregation or uniformity.

there is law of dominance and law of independent assortment.

In this case,it is the law of Dominance.

according to mendel when he worked with pea plants and performed both monohybrid cross(for 1 character) and dihybrid crosses(for 2 characters) he came to a conclusion stating that always when 2 parents having contrasting traits are crossed with each other the resulting offsprings will all express only a single type of phenotype. This phenotype is called as the dominant trait. IN the F1 generation, it is always the dominant trait being expressed and the trait that is not expressed or being suppressed is called as the recessive trait. It does not mean that the recessive trait is absent in the F1, it only means that it is not able to express itself in the F1 as a recessive trait needs to be in the homozygous state to express itself. IN the F1 all individuals are heterozygous. this was confirmed as the recessive trait reappears in the F2 generation.