Questions from previous Exam 2 material BioS 101

Lecture 1 Segregation of Alleles

In the F2 generation Mendel found that about 3/4ths of the peas were YELLOW and ¼ were GREEN. Mendel allowed the F2 peas to self and form an F3 generation. What proportion of the YELLOW F2 peas do you expect to have ALL YELLOW progeny?

a. none b. ¼ c. 1/3 d. ½ e. 2/3

If each progeny has a 3/4ths chance of being YELLOW and a ¼ chance of being GREEN, what is the probability that a pod with 3 peas has first two GREEN and the last one YELLOW?

a. none b. 1/64 c. 3/64 d. 9/64 e. 3/16

Lecture 2 Independent Assortment

If you expect 3/4ths of the progeny to be PURPLE and ¼ to be WHITE, calculate the Chi-Squared value, if the numbers observed were 80 PURPLE and 20 WHITE.

A. 0.75 B. 1.33 C. 2.33 D. 3.33 E. 3.84

Consider gamete formation in an individual with the Ab/aB genotype. If assortment is INDEPENDENT, which of the following is most likely to be true?

A. the proportion of Aa gametes will equal that of Bb gametes.

B. the proportion of AB gametes will equal that of Bb gametes.

C. the proportion of AB gametes will equal that of Ab gametes.

D. the proportion of AB gametes will equal that of Aa gametes.

E. all of the above

BioS 101 has 50% sophomores. The same class had 20% of the students earn a perfect 7 on problem set #2. If the grade on PS#2 is independent of year-in-school, what proportion of the class is expected to be a sophomore with a perfect score on the problem set?

a. 3.5% b. 5% c. 7% d. 10% e. 14%

Lecture 3 Genetic Hypothesis Testing

If there are three alleles at a locus, as is the case with the ABO blood type locus, how many different diploid genotypes are there?

A. three B. four C. six D. eight E. this situation is impossible.

Individuals with the dominant phenotype should be crossed with individuals with the _______ phenotype, if you want to test whether their genotype is ____________ or ___________.

A. recessive, recessive, dominant B. heterozygous, dominant, recessive

C. homozygous, heterozygous, homozygous D. recessive, heterozygous, homozygous

E. recessive, recessive, dominant

Lecture 4 Linkage of loci

A female is color-blind, a sex linked trait. Her mother is not color blind. Her father is colorblind. What is the probability that she got a gene causing the color blindness from her mother? (Assuming no exceptional genetic events)

a. 100% b. 25% c. 50% d. 75% e. this situation is impossible

An AB/ab individual will produce more __ and __ gametes than it produces __ and __ gametes.

(respectively, in order)

a. AB, ab, aB, Ab b. ab, Ab, aB, AB c. Ab, aB, ab, AB

d. AB, Ab, aB, ab e. Aa, Bb, aB, Ab

The diploid genotype Hq/hQ will produce _____ percent HQ gametes if the H locus is 20 map units from the Q locus?

a. 5% b, 10% c. 15% d. 20% e. 25%

Lecture 5 Disease & individuality

Sickle cell is a disease that is a consequence of the change of an amino acid in _______.

a. mosquitoes b. DNA c. red blood cell membrane

d. hemoglobin e. Plasmodium, a sporozoan

When phenotypic differences among humans are demonstrated to be due to genes, i.e., the ability to taste PTC, we describe (or characterize) the situation as a:

A. genetic polymorphism B. phenomorphism C. polyallelic

D. mutation E. monomorphism

A sex linked trait, such as hemophilia, is phenotypically manifest

A. more often in females B. more often in males

C. differs between the sexes, but which sex shows more differs according to the trait

D. in the gametes only E. can be transmitted only by females