Question

In a particular plant, genes A and B are completely linked. A plant of genotype A b/A b is crossed with one of genotype a b/a b. Which of the following is TRUE?

a) All the offspring will be AaBb
b) All the offspring will be AaBb or aabb
c) Half of the offspring will be AaBb and half will be aabb
d) All the offspring will be AaBb or AAbb

Answer 1

All offspring from the cross between a plant with genotype Ab/Ab and ab/ab will be Ab/ab due to the complete linkage of genes A and B.

Step-by-step explanation:

In the case where genes A and B are completely linked, a cross between a plant of genotype Ab/Ab with a plant of genotype ab/ab will result in all offspring having the genotype Ab/ab.

Since the genes are linked, they will be inherited together, and there will be no recombinant genotypes in the offspring.

The options a), c), and d) suggest combinations that would arise from independent assortment or recombination, which does not occur for linked genes. Therefore, the correct answer for the scenario described is b) All the offspring will be AaBb or aabb.