Zoo/Bot 3333
Genetics
Quiz 1
2/4/09
For answers to the quiz, click here:
Questions 1-2 pertain to the following. You have three jars containing the following
marbles:
Jar 1: 250 red and 750 white
Jar 2: 1 blue and 9 white
Jar 3: 40 green and 60 white
1. If you select 1 marble (without looking) from each jar, what is the probability of
choosing three white marbles?
a) 0.405; b) 0.738; c) 0.82; d) 0.99; e) none of the above.
2. If you select 1 marble (without looking) from each jar, what is the probability of
choosing at least 1 white marble?
a) 0.405; b) 0.738; c) 0.82; d) 0.99; e) none of the above.
Consider the following cross, where all the gene loci in question show simple Mendelian
patterns of inheritance and can be considered to assort independently of one another:
aaBbccDdEEFf x AaBbCcDdEeff
3. What fraction of the possible progeny will genotypically resemble the first parent
(i.e. aaBbccDdEEFf)?
a) 1/256; b) 1/64; c) 9/128; d) 27/128; e) none of the above.
4. What fraction of the possible progeny will phenotypically resemble the first parent?
a) 9/32; b) 27/64; c) 27/128; d) 81/128; e) none of the above.
5. For the genes in question, how many different types of gametes can be produced by
the first parent?
a) 4; b) 8; c) 32; d) 64; e) 128.
6. Which of the following statements is/are true?
I. The Pax6 gene of vertebrates and the eyeless gene of flies argue that the camera eye of
vertebrates and the compound eye of insects originated completely independently during
evolution.
II. Chymotrypsin and elastase are evolutionarily related to one another.
III. There are currently no laws in the U.S. that prohibit insurance companies from
denying coverage on the basis of the results of genetic tests.
IV. About one in every 2000 white Americans carries a recessive allele for cystic fibrosis.
a) I and II are true; b) I, II and III are true; c) II and III are true; d) all are true; e) only one
of the above statements is true.
The following pedigree is for a rare metabolic disorder in humans.
7. True or false: The above pedigree is most consistent with an autosomal dominant
pattern of transmission since it shows up in consecutive generations and males and
females are equally affected.
8. The most likely genotypes of individuals II-1 and II-2 in the above pedigree are
(respectively):
a) Aa and Aa; b) AA and Aa; c) AA and AA; d) Aa and aa; e) AA and aa.
9. In the above pedigree, the probability that individuals III-4 and III-5 would have a
child affected with the disorder would be:
a) 1/24; b) 1/16; c) 1/12; d) 1/4; e) none of the above.
10. Suppose individuals III-4 and III-5 gave birth to an affected child. Also suppose that
individuals III-1 and III-7 decided to get married. Under these circumstances, what
would be the probability that III-1 and III-7 would have a child affected with the
disorder?
a) 1/24; b) 1/16; c) 1/12; d) 1/4; e) none of the above.