Two organisms that are true-breeding for a certain genetic characteristic are mated and their offspring were analysed. Which of the following statements about this situation is correct?

Question

Two organisms that are true-breeding for a certain genetic characteristic are mated and their offspring were analysed. Which of the following statements about this situation is correct? (A) Both parents are homozygotes. (B) The offspring are either all homozygotes or all heterozygotes. (C) The offspring represent the F1 generation and the gametes produced by the offspring will carry only one allele for this gene. (D) All of the above

Tardigrade Admin · Accepted Answer

Given that both parents are true-breeding, the cross must be either AA × AA, AA × aa, or aa × aa. If you work out these crosses, you will see that all of the possible answers are true for each possible situation.

Q. Two organisms that are true-breeding for a certain genetic characteristic are mated and their offspring were analysed. Which of the following statements about this situation is correct?

Both parents are homozygotes.

The offspring are either all homozygotes or all heterozygotes.

The offspring represent the $F_{1}$ generation and the gametes produced by the offspring will carry only one allele for this gene.

All of the above

Given that both parents are true-breeding, the cross must be either $AA \times AA, AA \times aa$ , or $aa \times aa$ . If you work out these crosses, you will see that all of the possible answers are true for each possible situation.