A homozygous dominant brown mouse is crossed with heterozygous brown mouse. What percentage will the offspring be homozygous recessive? Use the letter "b"

A homozygous dominant brown mouse (BB) crosses with a heterozygous brown mouse (Bb)

What percentage might be homozygous recessive (bb) ?

If we draw a Punnett Square, we get BB, BB, Bb, and Bb.

Answer: 0% We don't have homozygous recessive. 50% is homozygous dominant and the other 50% is heterozygous.