Question

How are noncrossover offspring identified among a large population of offspring generated in a three-point mapping cross?

a. They have the same genotype as one of the parents
b. They have a unique genotype not present in either parent
c. They exhibit a high degree of genetic recombination
d. They exhibit a low degree of genetic recombination

Answer 1

Noncrossover offspring in a three-point mapping cross are those that show a low degree of genetic recombination, having the same genotype as one of the parents, thus reflecting the parental genotype.

Step-by-step explanation:

Noncrossover offspring in a three-point mapping cross can be identified because they exhibit a low degree of genetic recombination. These offspring have the same genotype as one of the parents, which means that no crossover occurred between the genes being examined.

This parental genotype is essential when mapping out the linkage of genes on chromosomes. Through the use of three-point mapping crosses, geneticists are able to determine the relative positions of genes on a chromosome and calculate recombination frequencies by observing the proportion of offspring that display nonparental genotypes.