BIOL 2153 Chapter : GenetHwrk2updated
Genetics 2153, Homework #2 (10 points total)
Due in Discussion Wednesday, February 8th.
Required Problems to hand in from book (4 points):
3.14 (use 2 test), 3.23, 4.8, 4.10, 4.18, 4.20, 4.26, 4.28. 19.2, 19.8
(Note: “phenotypic variance” is the amount of phenotypic variation—you don’t need to
know the detailed definition to do Q. 19.8)
Recommended: 3.12, 3.13, 4.1, 4.2, 4.3, 4.5, 4.7, 4.9, 4.11, 4.12, 4.13, 4.17, 4.19, 4.21, 4.25,
4.27, 4.28, 19.8.
Additional required problems (3 points each):
A. Using the information in problem 4.21 on the brown (br) and scarlet (sc) genes, How many
phenotypes will be produced in the progeny from a cross of a br+br sc+sc fly with a white-eyed
fly that has white eyes due to the recessive alleles br and sc? What are the different phenotypes
that will be produced? What proportion of the progeny will have each phenotype?
B. You have four colonies of mice that are independent of each other. Each has a true-breeding
mutation resulting in a short tail. For each colony, the short tail phenotype is recessive to the
wild-type long-tail phenotype. You do not know whether these four short tail phenotypes are
due to mutations in a single gene, or due to mutations in several different genes, and you decide
to find out. After performing all possible pairwise crosses of short-tailed mice among the
colonies (colony 1 mouse X colony 2 mouse, etc.), you find that all crosses give you long-tailed
mice with the wild-type phenotype. How many genes resulting in short tails are represented
among these four colonies?
Document Summary
Required problems to hand in from book (4 points): 3. 14 (use 2 test), 3. 23, 4. 8, 4. 10, 4. 18, 4. 20, 4. 26, 4. 28. 19. 2, 19. 8 (note: phenotypic variance is the amount of phenotypic variation you don"t need to know the detailed definition to do q. Recommended: 3. 12, 3. 13, 4. 1, 4. 2, 4. 3, 4. 5, 4. 7, 4. 9, 4. 11, 4. 12, 4. 13, 4. 17, 4. 19, 4. 21, 4. 25, What proportion of the progeny will have each phenotype: you have four colonies of mice that are independent of each other. Each has a true-breeding mutation resulting in a short tail. For each colony, the short tail phenotype is recessive to the wild-type long-tail phenotype. You do not know whether these four short tail phenotypes are due to mutations in a single gene, or due to mutations in several different genes, and you decide to find out. After performing all possible pairwise crosses of short-tailed mice among the colonies (colony 1 mouse x colony 2 mouse, etc.
