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"Problem 4-20:
Somatic cells of chimpanzees contain 48 chromosomes.
How many chromatids and chromosomes are present at (a) anaphase of mitosis, (b) anaphase I of meiosis, (c) anaphase II of meiosis, (d) G1 prior to mitosis, (e) G2 prior to mitosis, (f) G1 prior to meiosis I, and (g) prophase of meiosis I?
How many chromatids and chromosomes are present in (h) an oogonial cell prior to S phase, (i) a spermatid, (j) a primary oocyte arrested prior to ovulation, (k) a secondary oocyte arrested prior to fertilization, (l) a second polar body, and (m) a chimpanzee sperm? (1 point each)


Problem 4-24:
Imagine you have two pure-breeding lines of canaries, one with yellow feathers and one with brown feathers. In crosses between these two strains, yellow female x brown male gives only brown sons and daughters, while brown female x yellow male gives only brown sons and yellow daughters. Propose a hypothesis to explain these results. (3 points)

-----quite obviously colour of the canary is not a sex-linked trait.
else the males with yellow X would not have been brown and vice versa for the males with brown X chromosome.


Problem 4-26:
Each of the four pedigrees shown here represents a human family within which a genetic disease is segregating. Affected individuals are indicated by filled-in symbols. One of the diseases is transmitted as an autosomal recessive condition, one as an X-linked recessive, one as an autosomal dominant, and one as an X-linked dominant. Assume all four traits are rare in the population.
a. Indicate which pedigree represents which mode of inheritance, and explain how you know. (4 points)
b. For each pedigree, how would you advise the parents of the chance that their child (indicated by the hexagon shape) will have the condition? (1 point each)




Problem 4-36:
In Drosophila, the autosomal recessive brown eye color mutation displays interactions with both the X-linked recessive vermilion mutation and the autosomal recessive scarlet mutation. Flies homozygous for brown and simultaneously hemizygous or homozygous for vermilion have white eyes. Flies simultaneously homozygous for both the brown and scarlet mutations also have white eyes. Predict the F1 and F2 progeny of the following true-breeding parents: (3 points each)
a. vermilion females x brown males
b. brown females x vermilion males
c. scarlet females x brown males
d. brown females x scarlet males


Problem 4-40:
The ancestry of a white female tiger bred in a city zoo is depicted in the following pedigree. White tigers are indicated with unshaded symbols. (As you can see, there was considerable inbreeding in this lineage. For example, the white tiger Mohan was mated with his daughter). In answering the following questions, assume that hite?is determined by allelic differences at a single gene and that the trait is fully penetrant. Explain your answers by citing the relevant information in the pedigree. Could white coat color be caused by a: (2 points each)
a. Y-linked allele?
b. dominant X-linked allele?
c. dominant autosomal allele?
d. recessive X-linked allele?
e. recessive autosomal allele?
can you show me whatever you have, Thanks