Small tomatoes come in a variety of shapes.This problem involved four; round, oval, pear, and sausage. A tomato breeder crosses a true-breeding oval tomato with dark, blue-ish green, leaves with a true-breeding pear shaped (or beaked) tomato with plain green leaves.All the F1s have round tomatoes and green leaves.She then crosses these F1s with a homozygous recessive strain and get all the combinations of original phenotypes plus ones with sausage shaped tomatoes that are elongated though narrower at the top than the bottom.The numbers of offspring from the test-cross are below, and pictures of the tomato shapes below that.
Hint:To solve this problem work out all the genotypes first then set up in reciprocal pairs.
tomatoleaf
shapecolornumber
roundgreen23
rounddark green9
ovalgreen26
ovaldark green42
peargreen45
peardark green25
sausagegreen8
sausagedark green22
a) How is tomato shape inheriting?
b) Use letters such as A, B, D, E, where there is a clear difference between upper case and lower case to come up with genotypes for shape for the following
Original pear-shaped Parental:_________
Original oval-shaped parental:_________
Round tomato F1_________
Sausage-shaped test-cross offspring_________
b) Calculate genetic distances, use G for the leaf color gene name and draw a genetic map.