Zoo/Bot 3333
Genetics
Quiz #1
9/3/10
For the answers to the quiz, please 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 1-3, 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.
I.
The human Pax6 gene:
Is one example of how two totally different genes can be used for identical functions in closely-related
species.
II.
Is structurally related to a gene found in the Drosophila genome.
III.
Produces peaceful laid-back behavior 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.
Summarized his work in an 1866 paper that can be found in the OU History of Science collection.
III.
Was a contemporary of Charles Darwin.
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 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 is crossed to a purple-flowered wrinkled yellow seed
plant. The phenotypic ratios observed in the 80 offspring are: 31 purple-flowered, round, yellow seeds ; 10 purpleflowered, round, green seeds; 30 purple-flowered, wrinkled yellow seeds, and 9 purple-flowered, wrinkled, green
seeds. The genotypes of the parents are:
a) PpRrYy x PprrYy; b) ppRryy x PPRrYy; c) ppRrYy x PprrYy; d) ppRrYy x PPrrYy; e) none of the above.
5. A true-breeding variety of pea plant called Blue Persian produces a tall plant with blue seeds. Another truebreeding pea variety called Spanish Dwarf produces a short plant with white seeds. The two plants are crossed, and
the F1 seeds collected. They are all white, and when planted give rise to tall plants. The tall plants are allowed to
self fertilize. For these two traits, what phenotype would be found in the lowest numbers in the F2 generation?
a) white, tall; b) white, short; c) blue, short; d) blue, tall; e) all phenotypes should be found in equal numbers, since
this is a test-cross.
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 first 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 be genotypically resemble neither parent?
a) 9/32; b) 81/128; 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. 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.