Chapter 9, Problem 19PS

Summary Introduction

To imagine:

The deaf mates with a hearing female, we know the dead male must have the genotype dd, but the female could be either Dd or DD. Such a mating is essentially a testcross. If the parent’s first child can hear then what is the certainty the mother’s genotype must be. What if the couple has four children all with hearing- can you say with certainty the mother’s genotype. What would it take for a definitive genotype to be assigned.

Concept introduction:

The test cross is a type of cross between a homozygous recessive individual and heterozygous individual to determine the genotype of previous individual. This cross was given by Gregor Mendel.