In a Trihybrid Cross,the Expected Proportion of Offspring Showing All

Question

In a trihybrid cross,the expected proportion of offspring showing all three recessive traits is
A) 1/16
B) 1/64
C) 27/64
D) 9/16
E) 9/64

Accepted Answer

In a trihybrid cross (cross involving three traits), each trait segregates according to Mendel's laws, with a 3:1 ratio for each trait in the F2 generation. For an offspring to show all three recessive traits, it must inherit the recessive allele from both parents for each of the three traits. The probability of this happening is (1/4) * (1/4) * (1/4) = 1/64, because there is a 1/4 chance for each trait to be homozygous recessive (assuming complete dominance and independent assortment).