BIOL/PBIO 3333
Genetics
Quiz #1
9/3/14
For answers to the quiz, click here:
Please give the BEST answer for the following questions, using the digitized answer sheet provided. Please use
BLUE side of answer sheet for these problems.
For questions 1-4, please use the following code:
a) All of the statements are correct
b) I, II, and III are correct
c) I and III are correct
d) II and IV are correct
e) only IV is correct
1. The human Pax6 gene:
I.
Is one example of how two totally unrelated genes can undergo convergent evolution in mammals.
II.
Is structurally unrelated to genes that are found in the Drosophila genome.
III.
Produces a very peaceful laid-back personality in people and mice homozygous for Pax6 null mutations.
IV.
Will program other tissues to become eye tissue if expressed in those tissues during fruit fly development.
2. Gregor Mendel:
I.
Was an abbot in a monastery located in the present Czech Republic.
II.
Was a contemporary of Charles Darwin.
III.
Summarized a decade’s worth of work in a paper published and distributed to many libraries in Europe.
IV.
Was widely recognized in his lifetime as the “father of genetics”.
3.
I.
II.
III.
IV.
The smooth/wrinkled pea seed trait studied by Mendel:
Is mediated by an enzyme-encoding gene that was discovered by British scientists in the early 1990s.
Is mediated by a gene that encodes an ion channel protein, allowing water to enter the cell.
Is mediated by a gene that can be considered haplosufficient.
Is mediated by a gene located very close on the same chromosome to the yellow/green seed color trait.
4. In the picture on the right, which of the following are consistent with the observed
kernel phenotypes on this ear? (a color version of this picture is available online, but
B&W should suffice to answer this question)
I. The ear of corn shown represents F2 fertilization events from a dihybrid testcross.
II. The phenotype of kernel B should represent ¼ of all kernels on this ear.
III. Kernel C is showing a dominant phenotype for two different traits.
IV. The phenotype of kernels A and C should occur in equal numbers on this ear.
5. In peas, the allele for the round seed (R) trait is dominant to the wrinkled (r) trait, the allele for yellow seed color
(Y) is dominant to allele for green seed color (y), and the allele for purple flower color (P) is dominant to white
flower color (p). A white-flowered, round, yellow seed plant (parent 1) is crossed to a purple-flowered wrinkled
yellow seed plant (parent 2). The phenotypic ratios observed in the 80 offspring are: 17 purple-flowered, round,
yellow seeds ; 4 purple-flowered, round, green seeds; 16 purple-flowered, wrinkled yellow seeds, and 6 purpleflowered, wrinkled, green seeds; 12 white-flowered, round, yellow seeds; 16 white-flowered, wrinkled, yellow
seeds; 4 white-flowered, round, green seeds; 5 white-flowered, wrinkled, green seeds. The genotypes of the parents
(1 x 2) are:
a) PpRrYy x PprrYy; b) ppRryy x PPRrYy; c) ppRrYy x PprrYY; d) ppRrYy x PPrrYy; e) none of the above.
Questions 6-8 pertain to the following: Assuming independent assortment in the cross:
AaBbccddEe x AaBbCcDdEe
6. What proportion of the progeny will phenotypically resemble the second parent (AaBbCcDdEe) ?
a) 1/32; b) 9/128; c) 27/128; d) 27/256; e) none of the above.
7. What proportion of the progeny will phenotypically resemble either parent?
a) 1/32; b) 9/128; c) 27/128; d) 27/256; e) none of the above.
8. What proportion of the progeny will phenotypically resemble neither parent?
a) 9/32; b) 101/128; c) 15/16; d) 31/32; e) none of the above.
Questions 9-10 pertain to the following cross, following a rare disease gene in a human population. Assume that the
people marrying into the family are homozygous for the wild type allele:
?
9. The probability that individuals IV-1 and IV-2 first child would be affected is:
a) zero; b) 1/64; c) 1/36; d) 1/32; e) 100 percent.
10. Suppose the first child born to individuals IV-3 and IV-4 had the disorder. What are the odds that the next child
born to individuals IV-3 and IV-4 will be affected?
a) zero; b) 1/4; c) 1/2; d) 2/3; e) none of the above.
C