Biol 3Which of the following is not a trait of a Good Genetic Model System a. fast generation time b. has many redundant gene families c. inexpensive to culture d. Facile manipulation of genome e. has a large collection of mutants

2) A phenotype is

a. The complete compliment of genes in a species b. The outwardly manifested trait c. An individuals internally encoded trait as represented by specific

alleles d. A graphic display of inheritance patterns e. When a trait is not encoded by the nucleus

3) Variability in phenotype can be caused by

a. Differences in a single gene sequence b. Environmental factors c. Developmental noise d. Differences at Quantitative trait loci e. All of the above

4) In Meiosis, the stages of Prophase I are:

a. Leptotene, Zygotene, Pachytene, Diplosomia, Telekinesis b. Leptin, Zygotes, Polydactyl, Diplosomia, Diakinesis c. Leptotene, Zygotene, Pachytene, Diplotene, Diakinesis d. Leptin, Zygotes, Pachytene, Diplosomia, Diakinesis e. Leptotene, Zygosis, Polydactyl, Diplotene, Diakinesis

Question 5-7: Drosophila melanogaster have four pairs of chromosomes.

5) What is the ploidy level at Metaphase II of meiosis? a. 8n b. 1n c. 4n d. 2n e. 0n

6) How many chromatids are present per cell at Telophase I of meiosis?

a. 8 b. 16 c. 4 d. 2 e. 0

7) What is the ploidy level at Prophase of Mitosis?

a. 8n b. 4n c. 1n d. 2n e. 0n

Questions 8-11: Note that this question had a misspelled genotype. Also refer to the homework question for this. You have performed the following trihybrid test cross in maize with the colorless (c), waxy (wx) and shrunken (sh) loci. You need to figure out the map order and distance between the loci. Cc Wxwx Shsh X cc wxwx shsh (tester) Colored, Starchy, Plump colorless, waxy, shrunken You record the following progeny: Trihybrid Gamete Phenotype of

Progeny # of Progeny

C Wx Sh Colored, Starchy, Plump 4 c wx sh colorless, waxy, shrunken 2 c wx Sh colorless, waxy, Plump 2708 C Wx sh Colored, Starchy, shrunken 2538 c Wx Sh colorless, Starchy, Plump 626 C wx sh Colored, waxy, shrunken 601 c Wx sh colorless, Starchy, shrunken 116 C wx Sh Colored, waxy, Plump 113 Total 6708

8) Which of the following gamete genotypes is a parental (non-recombinant) class of the Trihybrid parent:

a. C Wx sh b. C Wx Sh c. C wx Sh d. C wx sh e. c Wx sh

9) Which of the following gametes represents a double recombinant event: a. C Wx sh b. C Wx Sh c. C wx Sh d. C wx sh e. c Wx sh

10) Which of the follow maps is correct:

e. is correct

11) Assume that the expected frequency of double recombinants is 0.00644. What is the coefficient of coincidence?

a. 0.36 b. 0.66 c. 0.001 d. 0.14 e. 1

Questions 12-13 You have identified a local family that is segregating for a common allergy to milk. The following is their pedigree:

12) Assuming complete penetrance, what is the mode of inheritance of this

trait? a. Autosomal Recessive b. Autosomal Dominant c. Sex-linked recessive d. Sex-influenced autosomal e. Cytoplasmic

13) What is the probability that the first child of IV-4 and IV-5 will have the milk allergy? Assume that III-6 is not a carrier.

a. 1/12 b. 1/6 c. 1/3 d. 1/2 e. 2/3

14) λ lysogens are immune to further infections by λ particles because: a. The λ receptors are clogged by the previous phage heads b. The E. coli host acquires a mutation that makes it immune c. The λ prophage produces a repressor protein that inhibits

phage replication d. The λ prophage produces an enzyme that cleaves the incoming

phage genome e. The E. coli host evolves resistance.

15) Consider a family that has five children. What is the probability that the four oldest children are girls and the youngest is a boy (GGGGB)?

a. 0.5 b. 0.05 c. (0.5)5 d. (0.5)4 + (0.5) e. 5 X (0.5)

16) What are the number of ways one can have 4 girls and 1 boy with only five children?

a. 1 b. 5 c. 10 d. 0.15625 e. 8

17) What is the probability that of five children, any four will be girls and one

will be a boy? a. (0.5)5 b. 8 X (0.5)5 c. 10 X (0.5)5 d. (0.5)5 + (0.5)5 + (0.5)5 + (0.5)5 + (0.5)5 [Note: also 5 X (0.5)5] e. 5 X (0.5)

18) Which form of inheritance best describes the following pedigree of a rare trait:

a. Autosomal Recessive b. Autosomal Dominant c. Sex-linked recessive d. Sex-influenced autosomal e. Cytoplasmic

19) Which of the following is the phenotypic ratio expected after a Dihybrid self cross with fully dominant alleles?

a. 3:1 b. 1:1:1:1 c. 9:3:3:1 d. 1:2:1:2:4:2:1:2:1 e. 9:4:3

20) Which of the following predictions would you make for a gene that is

found to be haplosufficient, but which is essential for viability in haploids?

a. A disruption allele would lead to nonviable haploid cells. b. A diploid heterozygous for a null allele and the wild-type allele will

be viable. c. A diploid heterozygous for a null allele and a wild-type allele will be

nonviable. d. a & b e. a & c

21) A single, visible colony of bacteria growing on an agar plate represents:

a. Approximately 1000 cells b. A population of aerobic bacteria, since anaerobic bacteria can’t be

grown on agar plate c. A mixture of several bacterial variants, due to slight differences in

DNA sequence introduced by mutations, but which all belong to the same species

d. A population of bacteria derived by multiple cell divisions from a single cell

e. a & d

22) When an F+ cell “mates” (conjugates) with an F- cell, which of the following is most likely to happen?

a. The original F+ cell becomes F- and the recipient F- cell becomes F+.

b. Both cells end up being F+. c. The F+ DNA always integrates into the chromosome of the F- cell

by homologous recombination. d. Both cells end up being resistant to ampicillin. e. Both cells end up being F′ strains.

23) Which of the following statements is not true? a. Genes are capable of existing in several states (alleles), each

having detectable effects. The change from one such state to another is known as mutation.

b. Each chromosome has many genes, and these are arranged in a linear order.

c. The order of genes along a chromosome is altered through the process of recombination.

d. Every gamete receives one chromosome of each homologous pair. This distribution of chromosomes to the gametes is a matter of chance.

e. The distribution to the gametes of the chromosomes of one homologous pair has no effect on the distribution of the chromosomes of the other pairs.

24) A temperature-sensitive allele:

a. Is expressed at the permissive temperature but not at the restrictive temperature

b. Is expressed at both the permissive and restrictive temperatures c. Encodes a protein that is functional at the permissive temperature

but nonfunctional at the restrictive temperature d. a and c e. b and c

25) To isolate an auxotrophic mutant in E. coli by indirect selection, a

researcher would best: a. Screen for colonies that grow on rich nutrient agar. b. Screen for colonies that grow on minimal medium + glucose. c. Screen for colonies that grow on rich nutrient agar but fail to

grow on minimal medium + glucose. d. Screen for colonies that grow in the presence of streptomycin. e. Screen for colonies that fail to grow in the presence of

streptomycin. Questions 26-27: You have found an ear of corn in which the kernels are either purple or yellow. You count and find that there are 110 purple kernels and 90 yellow kernels.

26) Assume the ear was the product of a monohybrid test cross. The χ2 value would be:

a. 0.2 b. 1 c. 2 d. 10 e. 42.667

27) Assume the ear was the product of a self cross of a dihybrid displaying complimentary gene action. The χ2 value would be:

a. 0.071 b. 0.127 (Note: Expect 9:7 ratio) c. 0.56 d. 42.667 e. 512.53

28) The genes A and B are 10 cMs apart. If the dominant alleles are in cis

in a dihybrid, the expected frequency of the ab gametes would be: a. 0.8 b. 0.1 c. 0.5 d. 0.05 e. 0.45

29) Which of the following statements about Specialized Transduction is

true: a. Can occur with any lytic phage. b. Is used to move plasmids into bacteria c. Is measured in minutes d. Phage particle contains mostly bacterial genes e. Only donor genes adjacent to the prophage insertion site are

transferred.

30) You have isolated several mutants in Caenorhabditis elegans that have

aberrant development of the vulva. Worms with abnormal vulvas can not lay eggs, and are easily scored since the eggs hatch within the hermaphrodite and wiggly about (bag-of-worms phenotype). The mutations are either vul for vulvaless, or muv for multiple vulvas. All of the mutations are recessive and are represented by a single allele. Given the following genotypes and their respective phenotypes, Which of the following pathways is correct? Assume all three genes are part of a signal transduction cascade.

Genotypes Phenotype vulA/vulA no vulva muvA/muvA multiple vulvas vulB/vulB no vulva vulA/vulA; muvA/muvA no vulva

vulB/vulB; muvA/muvA multiple vulvas

c. is correct

31) You have found the following pedigree of a family segregating for a

dominant hypersensitivity to iron (HI) in the diet. There is a microsatellite marker on the third chromosome you believed is linked to this HI. You find that there are three alleles for this microsatelite (M1, M2, and M3). After typing the family for this marker you develop the following pedigree:

The ratio of probability that the M1 marker is 10 map units from HI to that of the probability for independent assortment is:

a. 39.7 (note: Only 1 recombinant progeny. Linkage = [ 0.45]9 X

[0.05]; Ind. Assort. = [0.25]10). b. 40,356 c. 1.6 d. 0.25 e. 0.45

Question 32 and 33: You are interested in the genetic control of flower number in a population of cotton. The more flowers, the more cotton produced. From a self fertilization of a single plant with 22 flowers you find:

5 plants with 1-2 flowers 20 plants with 11-12 flowers 30 plants with 22-24 flowers 20 plants with 33-36 flowers 5 plants with 45-48 flowers

32) The most likely explanation for this inheritance is:

a. A dihybrid segregating two quantitative trait loci (note: Best explains five phenotypic classes with additive differences)

b. A monohybrid segregation an incompletely dominant trait c. A dihybrid showing dominant epistasis d. A monohybrid with 75 % penetrance. e. Variable expressivity

33) If you were to test this hypothesis with 5 groups by χ2 analysis, the

degrees of freedom would equal: a. 0.2 b. 1 c. 4 d. 5 e. 10

34) 2) Which of the following is NOT a difference between RNA and DNA?

a) Sugar – ribose vs. deoxyribose b) 3’-OH c) 2’-OH d) Base - Uracil vs. Thymine e) None of the above.

3) Which of the following is NOT TRUE regarding the processing of the 3’ end of RNA transcripts?

a) Is modified by the addition of 7-methyl guanosine cap. b) Is modified by the addition of a polyA tail. c) Has a polyadenylation signal; AAUAAA or AUUAAA, near the 3´ end of the transcript. d) all are true

5) In what cellular compartment are introns removed from pre-mRNA to make mature mRNA?

a) Cytoplasm b) Endoplasmic Reticulum c) Nucleus d) Mitochondia e) Golgi apparatus