Question

Genes A and B are on the same chromosome. If a person has one chromosome with the alleles AB and a second chromosome with the alleles ab, how could they produce a gamete with a chromosome containing the alleles Ab or aB?

a) Independent assortment
b) Random fertilization
c) Mitosis
d) Fragmentation of the chromosome
e) Crossing over

Answer 1

A person with AB and ab alleles on homologous chromosomes can produce gametes with Ab or aB alleles through the process of crossing over during prophase I of meiosis.

Step-by-step explanation:

The individual with one chromosome containing the alleles AB and another with ab can produce gametes with the alleles Ab or aB through a process known as crossing over. This genetic recombination occurs during prophase I of meiosis when homologous chromosomes pair up and exchange segments, leading to new combinations of alleles in the resulting gametes.

Therefore, although genes A and B are on the same chromosome and are usually inherited together, crossing over can separate them so that gametes can end up with recombinant alleles such as Ab or aB, instead of just the parental AB or ab configurations.