What offspring do homozygous individuals give during self-pollination?

Organisms can be homozygous for both the gene for the dominant trait and for the gene for the recessive trait.

Let the dominant trait gene be B and the recessive trait gene b.

Individuals BB homozygous for the dominant gene produce the same type of germ cells B. When they are crossed with each other, all offspring will have the same genotype as the parental individuals – BB and exhibit a dominant trait.

It is the same with individuals homozygous for the recessive gene bb. They produce the same type of gametes b. All offspring are homozygous bb individuals showing manifestations of a recessive trait.