Assume that plant weight is determined by a pair of alleles at each of two independently assorting loci (A and a, B and b) that are additive in their effects. Further assume that each allele represented by an uppercase letter contributes 4 g to weight and that each allele represented by a lowercase letter contributes 1 g to weight. a. If a plant with genotype AA BB is crossed with a plant with genotype aa bb, what weights are expected in the F1 progeny?

10 g

Explanation:

In the given question, the uppercase letters that are A and B contribute 4 g of weight whereas the lowercase letters a and b contributes 1 g of weight.

When a cross is made between

                                          AABB     x       aabb

alleles will be-                   AB                   ab

F₁ progeny will be-           AaBb

In F₁ progeny, all offsprings will be AaBb.

The weight of the offsprings will be 4+1+4+1

= 10 g

Thus, 10 g is the correct answer.