Biology 1001A Study Guide - Cyclic Adenosine Monophosphate, Melanocortin 1 Receptor, Allele Frequency

Q5. A sunflower population in Hardy-Weinberg equilibrium has the following allele frequencies for petal color: 0.75 dominant, 0.25 recessive. If the assumptions of Hardy-Weinberg equilibrium continue to hold, then after 200 generations:

The allele frequencies will be: 0.75 dominant and 0.25 recessive.

The allele frequencies will be: 0.50 dominant and 0.50 recessive.

The allele frequencies will be: 1.0 dominant and 0 recessive. T

here is no way to predict allele frequencies, given the information provided.

Q6. Mead and his colleagues proposed a hypothesis for the apparent heterozygote advantage for the PrP locus. What did they suggest as the basis for the high presence of both alleles?

History of cannibalism.

Protection from malaria.

Protection against plague.

They did not propose a heterozygotic advantage for the PrP locus.

Q7. A frog population has two alleles for skin color at the following relative frequencies: Allele SC1= 0.8, Allele SC2 = 0.2. Allele SC2 is:

Dominant

Recessive

Co-dominant

Impossible to determine dominance from the information given.

Q8. A bird population has two alleles for feather color at the following relative frequencies: Allele FC1 = 0.5, Allele FC2 = 0.5. Allele FC1 is:

Dominant

Recessive

Co-dominant

Impossible to determine dominance from the information given.

Q9. Use the following information for both questions 9 and 10: You encounter a few populations of millipedes with variation in skin color. Genotype can be inferred from coloration: CC millipedes are black, Cc millipedes are brown, and cc millipedes are yellow. [You can launch a calculator byclicking here.] If one millipede population has 60 black individuals, 20 brown individuals, and 20 yellow individuals, what is the relative frequency of allele C in that population?

0.5

0.6

0.7

0.8

Impossible to calculate from the information given.

Q10. If another millipede population's allele frequencies are 0.5 for C and 0.5 for c, what is the expected frequency of the cc genotype in the population, if the population is in Hardy-Weinberg equilibrium?

0.125

0.25

0.5

1.0

Impossible to calculate from the information given.

1 A) Cystic Fibrosis is an autosomal recessive disease, 1 out of every 2500 individuals of Caucasian descent in the US have cystic fibrosis. What frequency of cystic fibrosis carriers would you expect in the Caucasian population of the US under Hardy Weinberg Equilibrium? Show your work. (1 pt)

1 B) You know that penguin tuxedo color is a classic Mendelian single-gene trait, the allele for black and white tux coloring (T) is dominant over gray and white tux coloring (t). In a population of penguins, there are 400 black and white tuxedoed penguins and 200 gray and white tuxedoed penguins.

(i) Which observed genotypic or allelic frequencies can be calculated from this scenario without assuming Hardy Weinberg Equilibrium? (1.5 pt)

(ii) In one to two sentences, explain why differences may arise between observed and expected genotype frequencies. (1 pt)

1 C) You are studying inheritance of external keratin features in a dinosaur. Analysis has found that the presence of feathers is due to codominance between the AS (scales) and AH (horns) alleles. In one generation of a population you find 78 scaled dinosaurs, 76 feathered dinosaurs, and 64 horned dinosaurs.

(i) What are the observed allele frequencies of AS and AH ? Use p for the frequency of AS and q for the frequency of AH . Show your work. (1.5 pt)

(ii) What are the observed genotypic frequencies? Show your work. (1 pt)

(iii) Given the allelic frequencies calculated above, what are the expected number of scaled, feathered, and horned dinosaurs in a population of the same size (218) under Hardy Weinberg Equilibrium? Show your work. (1.5 pt)

(iv) Use a chi-square test to examine whether the gene you are studying is under Hardy Weinberg Equilibrium in this population. Show your work. Do you accept or reject the null hypothesis? (2 pts)