Question 1
Assume that a cross is made between
AaBb and
aabb plants and that the offspring occur in the following numbers: 106
AaBb, 48
Aabb, 52
aaBb, 94
aabb. These results are consistent with which arrangement of alleles?
Question 2
In the fruit fly,
Drosophila melanogaster, a spineless (no wing bristles) female fly is mated to a male that is claret (dark eyes) and hairless (no thoracic bristles). Phenotypically wild-type F
1 female progeny were mated to fully homozygous (mutant) males, and the following progeny (1000 total) were observed:
| Phenotypes | Number Observed |
| hairless, claret, spineless | 32 |
(a) Which gene is in the middle?
(b) With respect to the three genes mentioned in the problem, what are the genotypes of the homozygous parents used in making the phenotypically wild-type F
1 heterozygote?
(c) What are the map distances for the three genes? A correct formula with the values "plugged in" for each distance will be sufficient.
(d) What is the coefficient of coincidence? A correct formula with the values "plugged in" will be sufficient.
Representative fruit types
Female Hector's dolphin jumping off Banks Peninsula, New Zealand
Procedures and Diagnostic Tests Related to the Female Reproductive System
Two reciprocal Drosophila crosses performed by Morgan