Question

value: 10
two moths mate and produce bollworm caterpillars that are bt - resistant and bt - susceptible. bt - resistant is an autosomal recessive trait. what are possible genotypes of the parents?
a. rr, rr
b. rr, rr
c. rr, rr
d. rr, rr
value: 10
a man has red green colorblindness. which parent did the disorder come from?
a. mother
b. father
c. could have come from either parent

Explanation:

1. For the first question about Bt - resistance: Since Bt - resistant is an autosomal recessive trait (rr), and the parents produce both Bt - resistant (rr) and Bt - susceptible (RR or Rr) offspring, both parents must be carriers (Rr) because only when both parents are Rr can they produce rr offspring through the combination of their gametes.
2. For the second question about red - green colorblindness: Red - green colorblindness is an X - linked recessive disorder. Males have one X and one Y chromosome (XY). The Y chromosome comes from the father and the X chromosome comes from the mother. So, a man with red - green colorblindness must have received the mutant allele on the X chromosome from his mother.

Answer:

1. b. Rr, Rr
2. a. mother