A lethal allele causes death, frequently at an early developmental stage, and so one or more genotypes are missing from the progeny of a cross. Lethal alleles modify the ratio of progeny resulting from a cross.
-A cross between two green corn plants yields 2/3 progeny that are green and 1/3 progeny that are white. What is the genotype of the green progeny?
A) WW
B) Ww
C) ww
D) W_ (WW and Ww)

Question

Quizplus · Accepted Answer

The green progeny have the genotype Ww. The 2:1 ratio of green to white progeny suggests that the WW genotype is lethal, and only Ww (green) and ww (white) survive.

A Lethal Allele Causes Death, Frequently at an Early Developmental