In the snail, Limnaea peregra , the direction of shell coiling is a maternal eff
ID: 177368 • Letter: I
Question
In the snail, Limnaea peregra, the direction of shell coiling is a maternal effect trait. If right coiling (D) is dominant to left (d) coiling which of the following statements is true if a left coiling Dd female mates with a right coiling Dd male?
all of the F1 progeny will coil to the right
all of the F1 progeny will coil to the left
3/4 of the F1 progeny will coil to the right and 1/4 of the F1 will coil to the left
1/4 of the F1 progeny will coil to the right and 3/4 of the F1 will coil to the left
F1 progeny coiling will depend on the genotype of the Dd female’s mother
a.all of the F1 progeny will coil to the right
b.all of the F1 progeny will coil to the left
c.3/4 of the F1 progeny will coil to the right and 1/4 of the F1 will coil to the left
d.1/4 of the F1 progeny will coil to the right and 3/4 of the F1 will coil to the left
e.F1 progeny coiling will depend on the genotype of the Dd female’s mother
Explanation / Answer
b) all of the F1 progeny will coil to the left. This is because the direction of shell coiling is a maternal effect trait. For this we need not see which trait is dominant over the other.