GEN Exam 1-4 Questions

Which is not a desired characteristic of model organisms?

a. rapid life cycles

b. large genome size

c. small in size

b

The area of genetics interested in how traits are passed on from parents to their offspring is known as what?

a. transmission genetics

b. molecular genetics

c. population genetics

a

The central dogma of molecular biology is:

a. protein -→ translation -→ RNA -→ transcription -→ DNA

b. DNA -→ translation -→ protein --→ transcription -→ RNA

c. DNA -→ transcription -→ RNA -→ translation -→ protein

c

DNA replication takes place in which phase of the cell cycle?

a. M phase

b. S phase

c. G1

d. G2

b

In humans, which is the heterogametic sex?

a. males

b. females

c. hermaphrodites

a

Which is a y-linked trait?

a. huntington’s disease

b. color blindness

c. maleness itself

c

Which is the monohybrid?

a. A/a x A/a

b. A/A x a/a

c. A/a x B/b

a

Which is the dihybrid?

a. A/a \* B/b

b. A/A \* B/b

c. A/a \* B/B

d. a/a \* b/b

a

Which is the cross that would yield progeny that are 100% dihybrids?

a. A/A\*B/B x a/a \*b/b

b. A/a\*B/b x A/a\*B/b

c. a/a\*B/B x A/a\*B/b

a

The “A” allele is dominant to the “a” allele. What cross would produce a 1:1 phenotypic ratio among the progeny?

a. A/a x A/a

b. A/A x a/a

c. A/a x a/a

c

Assume you cross 2 pure breeding strains of roses to generate monohybrid offspring. Selfing the monohybrids gives rise to a 3:1 phenotype ratio. The generation of roses with the 3:1 phenotype ratio is referred to as what?

a. parental (P)

b. F1

c. F2

c

Which of these plants would breed true if selfed?

a. A/a \* B/b

b. A/A \* b/b

c. A/a \* B/B

b

What phenotype ratio would you expect to result from a dihybrid cross?

a. 1:1:1:1

b. 9:3:3:1

c. 3:1

d. 1:2:1

b

The gametes of Mendel’s pea plants, humans, and flied are all

a. diploid

b. triploid

c. haploid

c

In bees, one a+ allele is enough to give rise to the normal antenna phenotype. The a+ allele is

a. haplosufficient

b. haploinsufficient

c. both

\

a

Two gametes with the genotypes T, Q and t, q came together to form a dihybrid offspring. When that offspring makes gametes with the genotype T, q or t, Q those gametes can be referred to as:

a. dihybrids

b. monohybrids

c. recombinants

c

Different version of the same gene are called

alleles

a plant cell with 2 different genotypes of chloroplasts DNA is called a

cytohet

mitochondrial DNA is inherited through which biological sex?

maternal

produces 4 haploid cells

meiosis

produces 2 haploid cells

mitosis

directly results in most cells of the body

mitosis

results in gametes

meiosis

daughter cells genetically identical to parent cells

mitosis

homologous chromosomes move to opposite poles during anaphase

meiosis

When one gene masks or alters the expression of another gene, it is known as:

a. crossover

b. vertical transfer

c. epistasis

d. hybrid vigor

c

if a true breeding red flying squirrel is crossed with a true breeding yellow one, and all their offspring are orange, this is an example of:

a. codominance

b. incomplete dominance

c. epistasis

d. no interaction between genes

b

the varying levels of phenotypic presentation in a population is known as

a. penetrance

b. expressivity

c. phenotypic value

d. codominance

b

What is the purpose of conducting a complementation test?

a. to determine if the products of 2 genes interact and complement one another

b. to determine if 2 mutations that affect the same phenotype are in different genes

c. to determine if 2 genes are linked on the same chromosome

b

The genetics of human blood type is an example of?

a. incomplete dominance

b. codominance

c. haploinsufficiency

d. dominant negative

b

When DNA is transmitted from mother cell to daughter cell during mitosis, this is an example of:

a. diagonal transmission

b. horizontal transmission

c. vertical transmission

c

Transmission of DNA requiring cell-cell contact and a pilus is called:

a. conjugation

b. transformation

c. transduction

a

When one mutant allele is sufficient for the expression of a mutant phenotype, even if there is one good wild type allele, this is called

a. haplosufficiency

b. dominant negative

c. incomplete dominance

b

The phenotypic ratio indicative of a recessive lethal allele is

a. 1:1

b. 3:1

c. 4:1

d. 2:1

d

A mutation that rescues the effects of another mutation is called a

a. suppressor

b. dominant recessive

c. synthetic lethal

a

Two genes possess mutant alleles. The double mutant is lethal. What phenotypic frequency do you expect from a dihybrid cross for these 2 genes?

a. 9:3:3:1

b. 1:1:1:1

c. 3:1

d. 9:3:3

d

Hfr strains have F factors which are active during conjugation. The “F” in F factor stands for:

a. force

b. fertility

c. frequency

d. familial

b

Summer squash come in 3 different colors. White, yellow or green. Gene Y determines if the fruit produces yellow (Y/-) or green (y/y) pigment. However, if the plant is W/- at the w locus, it will be white and will not express the color encoded at the Y locus. What is this an example of?

a. recessive epistasis

b. dominant epistasis

c. genes in the same pathway

d. dominant negative

a

Which of the following is not a molecular marker?

a. SNPs

b. microsatellites

c. alleles

d. minisatellites

c

dihybrid test cross ratio

1:1:1:1

monohybrid test cross ratio

1:1

dihybrid selfed ratio

9:3:3:1

monohybrid self ratio

3:1

Recessive epistasis ratio

9:3:4

dominant epistasis ratio

12:3:1

genes in the same pathway/ duplicative recessive epistasis ratio

9:7

no gene interaction ratio

9:3:3:1

In genetics when one phenotype “stands upon” another phenotype, we call this?

epistasis

write 2 genotypes that can be used for a monohybrid cross

A/a x A/a

crossing over happens during what phase of meiosis?

prophase 1

When a prototroph mutates and can no longer grow on minimal medium. We call this new strain

auxotrophic

crossing over occurs at chromosomal conformations called

chiasmata

You observe two genes that a recombination frequency of 0.21. How many map units separates there two genes?

21

viruses that infect bacteria are called

bacteriophage

the tube like structure that connects two bacteria during conjugation is called a

pili

the generic term for a small circular DNA molecule that contains genes encoding resistance to antibiotics that bacteria may exchange directly or obtain from the environment is called a

R plasmid

Auxotrophic bacterial strains require some form of supplementation in their medium in order to grow. Wild type trains that do not require such supplementation are called

protorophic

Performing a complementation test with two mutant parents produces offspring with the wildtype phenotype. The parent mutations are in

2 genes

maps based on DNA sequencing are called

physical maps

Complete the word. In cases where two wild type alleles are necessary to produce the wild type phenotype, we call this haplo---------------

insufficient

You are working with a dihybrid cross that produces three phenotypic classes. You run a chi square test with the hypothesis that the two genes are unlinked. How many degrees of freedom do you have

3

Organisms that possess a nucleus and other organelles are called eukaryotes. Bacteria and archaea , which lack these structures, are called

prokaryotes

If 25% of the nucleotides in a string of DNA are guanines, what proportion will be cytosines?

a. 25%

b. 50%

c. 12.5%

a

During dna replication, what enzyme is responsible for synthesizing RNA primers?

a. RNA polymerase I

b. gyrase

c. primase

d. RNA polymerase II

c

When bacteria take up DNA from the environment this is called

a. transduction

b. transformation

c. transfection

b

What is the site where all charged tRNAs except the initiator tRNA enter the ribosome?

a. E site

b. A site

c. P site

d. peptidyl-transferase center

e. decoding center

b

Which molecules comprise the ternary complex?

a. EF-Tu

b. EF-G

c. charged tRNAs

d. uncharged tRNAs

a, c

Who contributed the X-ray crystallography data needed to determine the structure of DNA but did not receive the Nobel prize of the discover?

a. Rosalind Franklin

b. James Watson

c. Francis Crick

d. Jaque Monod

a

The mechanism of DNA replication is

a. conservative

b. dispersive

c. semiconservative

d. liberal

c

This sequence is present in the 5’ untranslated region (UTR) of all prokaryotic mRNA transcripts and forms base pairs with the 16S rRNA of the subunit, thus aligning the mRNA and the rRNA correctly

a. anticodon

b. codon

c. shine-Dalgarno sequence

d. -10 and -35 consensus sequences

c

What is the site where peptide bonds are formed?

a. E site

b. A site

c. P site

d. peptidyl-transferase center

e. decoding center

d

Okazaki fragments are associated with what strand of DNA during replication?

a. leading strand

b. lagging strand

b

Which protein helps move charged tRNAs to the P site during translation?

a. EF-Tu

b. EF-G

c. IF2

d. RF1

b, c

What stage of transcription does RNA splicing occur?

a. initiation

b. elongation

c. termination

b

These two proteins function in eukaryotic DNA replication and ensure that it only takes place during S phase

a. RNA polymerase II and sigma factor

b. ctd6 and ctd1

c. topoisomerase and B clamp

b

added to 5’ end of mRNA in eukaryotes

5’ cap

added to the 3’ end of mRNA in eukaryotes

poly A tail

binds -35 and -10 consensus sequences

sigma factor

two ways of termination of transcription

intrinsic and rho dependent

phosphorylating this begins elongation

carboxy terminal domain

prevents translation of a specific transcript

siRNA

genes that are always expressed

constitutive

bonds that hold together amino acids in a polypeptide

peptide bonds

the genetic code is

nonoverlapping

has binding site for both tRNAs and amino acids

amino acid tRNA synthetases

can form base pairs with both A and G

uracil

large complexes involved in protein synthesis

ribosomes

ribosomal small subunit rRNA in eukaryotes

18S

ribosomal small subunit rRNA in prokaryotes

16S

the aminoacyl site of the ribosome

A site

the peptidyl site of the ribosome

p site

the exit site of the ribosome

e site

In eukaryotes, these are spliced out of mRNA before translation

intron

this enzyme ensures that chromosomes do not get shorter after each round of DNA synthesis

telomerase

What enzyme joins DNA fragments together by repairing the DNA backbone?

DNA ligase

Which 2 nucleotides are common in the origins of replication in both E. coli and yeast?

A and T

What type of RNA moleucle has an anticodon?

tRNA

the large molecular complex that is compromised of both RNA and proteins that accomplishes protein synthesis in the cell is called a

ribosome

which nitrogenous base is unique to RNA as compared to DNA?

uracil

The system of adaptive immunity in bacteria that has been harnessed for gene editing in eukaryotes is called

CRISPR