Final Clicker Q's

Question 1

CdKs are activated:

a) by protein phosphatases
b) when they bind to another protein
c) by the addition of sugar groups (glycosylation)
d) when the interact with a ligand-bound cell surface receptor

Answer 1

B) when they bind to another protein

Question 2

Communication between cells is analogous to communication between people. Which form of intercellular communication is most like a landline
telephone call?
a) Paracrine signaling b) Synaptic signaling c) Hormonal signaling

Answer 2

Synaptic Signaling

Question 3

Communication between cells is analogous to communication between people. Which form of intercellular communication is most like conversation at a party?
a) Paracrine signaling b) Synaptic signaling c) Hormonal signaling

Answer 3

Paracrine signaling

Question 4

Considering the DNA strand on the right, a new
deoxynucleotide could be added: (strand is a 3’ end to 5’ end)
a) on the top
b) on the bottom
c) on either the top or bottom

Answer 4

A) On the TOP

Question 5

Consider the following primer/template pair: ATGACTA
3’AACTACTGATGAC5’
The newly synthesized DNA will be:
a) 5’AAC3’ b) 5’GAC3’ c) 5’GTT3’ d) 5’CTG3’

Answer 5

D) 5’CTG3’

Question 6

Consider the following template strands of DNA:
3’ to 5’ above
5’ to 3’ below
Which template strand would allow DNA synthesis to move from right to left?
a) the upper strand b) the lower strand c) both strands
d) neither strand

Answer 6

B) the lower strand

Question 7

Crossing over creates all possible combinations of maternal and paternal chromosomes in gametes.

a) True
b) False

Answer 7

B) False

Question 8

The default sex in mammals is: a) female

b) male
c) hermaphrodite

Answer 8

A) Female

Question 9

A diploid cell with 4 chromosomes in all enters meiosis. At the completion of meiosis each daughter cells will contain _____ chromosomes and ________ DNA molecules.

a) 2; 2
b) 2; 4 c) 4; 2 d) 4;4 e) 4;8

Answer 9

A) 2; 2

Question 10

For metaphase to move properly to anaphase: a) the chromosomes should start to condense b) the mitotic spindle should begin to form
c) each kinetochore should be attached to a spindle
fiber
d) sister chromatids should be moving to future daughter nuclei

Answer 10

A) the chromosomes should start to condense

Question 11

Histone acetyl transferases are the enzymes that add acetyl groups to histones. If a histone acetyl transferase became overactive, you’d predict that:

a) DNA at enhancers would be opened into a transcription bubble
b) DNA at replication origins would be opened into a replication bubble
c) chromatin would be in a relaxed, transcriptionally competent state
d) chromatin would be in a condensed, transcriptionally incompetent state
e) RNA processing, particularly splicing, would speed up

Answer 11

C) chromatin would be in a relaxed, transcriptionally competent state

Question 12

Hormones are ligands. True or False?

Answer 12

True

Question 13

How many genetically distinct gametes could be produced
by an individual with the genotype AABbccDd? a) 2
b) 3 c) 4 d) 8 e) 16

Answer 13

C) 4

Question 14

A human cell prior to mitotic division contains 46 chromosomes. Immediately after mitosis, each human nucleus contains ___________ chromosomes and ____________ DNA molecules.
a) 23; 46 b) 46; 46 c) 46; 92 d) 92; 92 e) 92; 184

Answer 14

B) 46; 46

Question 15

Human nuclei contain 46 chromosomes. Therefore, just
before mitosis, each nucleus contains ____________ molecules of DNA.
a) 23
b) 46
c) 92
d) 184

Answer 15

C) 92

Question 16

The idea that genome sizes of multicellular eukaryotes vary widely, but there is relatively little difference between the number of genes implies that:

a) the number of genes per unit length of DNA varies widely among eukaryotes
b) eukaryotes with larger geneomes tend to be more complex c) genome sizes have contracted over evolutionary time
d) genome size have expanded over evolutionary time

Answer 16

A) the number of genes per unit length of DNA varies widely

Question 17

If a DNA molecule contains 20% of its bases as G, then the
percentage of bases that are T is:
a) 20%
b) 25% c) 30% d) 35% e) 40%

Answer 17

C) 30%

Question 18

If a mutation occurred that lowered the amount of Ced- 9, this would be predicted to ______ the number of cells that undergo apoptosis.

a) increase
b) decrease
c) have no effect on

Answer 18

A) Increase

Question 19

If an mRNA encoded a 300 amino acid protein, how
long would the coding region be? a) 300 nucleotides
b) 600 nucleotides c) 900 nucleotides

Answer 19

C) 900 nucleotides

Question 20

If you found an E. coli cell is found with many short DNA fragments that started with RNA sequences, you should suspect that there is a deficiency in:

a) DNA ligase activity
b) DNA polymerase I activity c) DNA polymerase III activity d) helicase activity

Answer 20

B) DNA polymerase I activity

Question 21

Imagine the following: You examine proteins in a cell and
find one protein that is phosphorylated to unusually high levels. A plausible explanation is that:
a) a protein phosphatase is inactive b) a protein kinase is overly active c) the cell is unable to produce ATP d) a and b
e) all the above

Answer 21

D) A and B

Question 22

Imagine transplanting an undifferentiated cell in an early embryo that would normally form muscle into a region of another embryo that normally forms skin. This transplanted cell differentiates into a muscle cell in its new location. This is evidence that the transplanted cell was:

a) apoptotic
b) determined c) differentiated

Answer 22

B) determined

Question 23

In a search for drugs that work against HIV (the “AIDS virus”) without harming our cells, a reasonable drug target would be:

a) RNA polymerase
b) DNA polymerase
c) reverse transcriptase d) the ribosome

Answer 23

C) reverse transriptase

Question 24

In lentils, a gene known as spotted has two alleles. The A1 allele leads to large spots on lentil seeds and the A2 allele leads to small dots on lentil seeds. A cross between an A1A1 spotted variety and an A2A2 dotted variety produced an F1 that had spots and dots on the seed. Therefore, the A1 and A2 alleles are related by:

a) complete dominance b) incomplete dominance c) codominance
d) none of the above

Answer 24

C) codominance

Question 25

In plants, gametes are produced by mitotic cell divisions.

a) True
b) False

Answer 25

A) True

Question 26

In plants, meiosis produces:
a) haploid cells that divide by mitosis to produce a
multicellular plant.
b) diploid cells that divide by mitosis to produce a multicellular plant.
c) haploid gametes.
d) diploid gametes.

Answer 26

A) haploid cells that divide by mitosis to produce a multicellular plant

Question 27

In the context of gene duplication and divergence, if the rate of point mutation were reduced, which of the following would be most affected?

a) gene deletion
b) gene duplication
c) gene divergence

Answer 27

C) gene divergence

Question 28

In the following cross, the dominant phenotype can first be determined by examining the phenotype (s) of the:
P Generation: Purple x White Flowers
F1: All plants had purple flowers
F2: 705 Purple Flowers, 224 White Flowers
a) parents b) F1
c) F2

Answer 28

B) F1

Question 29

A liver cell is expected to contain a control
element needed to regulate the expression of a
protein found only in nerve cells. a) True
b) False

Answer 29

A) True

Question 30

Many segments of DNA are not parts of
genes.
a) True
b) False

Answer 30

A) True

Question 31

Mendel also performed the following cross: Purple flowers (Pp) x White flowers (pp)
What is the predicted outcome in the offspring? a) all purple
b) all white
c) 1 purple: 1 white
d) 3 purple: 1 white e) 1 white: 3 purp

Answer 31

C) 1 purple: 1 white

Question 32

Micro-RNAs work to control gene expression: a) before transcription occurs

b) after transcription but before translation occurs
c) after translation has occurred
d) by controlling the rate of protein degradation

Answer 32

B) after transcription but before translation occurs

Question 33

Mitosis and meiosis can only occur starting with diploid cells.

a) True
b) False

Answer 33

B) False

Question 34

Most nuclear responses to a cell signal

involve a change in enzyme activity. True or False?

Answer 34

False

Question 35

MyoD is likely to bind to: a) a promoter

b) a start codon
c) an enhancer
d) an exon
e) an intron

Answer 35

C) an enhancer

Question 36

A nonsense mutation in a proto- oncogene would be
likely to create an oncogene. a) True
b) False

Answer 36

B) False

Question 37

Only the receptor bound to ligand interacts with the first protein in
a signal transduction cascade. This is because:
a) the receptor delivers the ligand (signal) to the signal
transduction protein
b) the receptor is ionized
c) the degree of ionization of the receptor is reduced d) the ligand-bound receptor has the proper shape

Answer 37

D) the ligand-bound receptor has the proper shape

Question 38

Predict the gamete genotypes that would form if the genes below assorted independently.

a) 1 b+ vg+: 1 b vg
b) 3 b+ vg+: 1 b vg
c) 9 b+ : 3 vg+: 3 b : 1 vg
d) 1 b+ vg+: 1 b+ vg : 1 bvg+ : 1 bvg

Answer 38

D) 1b+ vg+: 1 b+ vg: 1 bvg+ : 1bvg

Question 39

The promoter is:

a) a sequence in DNA
b) a protein that binds to DNA c) RNA polymerase

Answer 39

A) a sequence in DNA

Question 40

Red-green colorblindness is a human X-linked recessive trait. If a colorblind man marries a colorbliness carrier woman, what is the chance that their first child will be colorblind?
a) 0 b) 1⁄4 c) 1⁄2 d) 3⁄4 e) 1

Answer 40

C) 1/2

Question 41

A signal binding to the same type of receptor will always lead to the same
cellular response. True or False?

Answer 41

False

Question 42

Silent mutations are possible because of:

a) the degeneracy of the genetic code
b) the use of three different stop codons
c) the non-overlapping way codons are read d) the fact that codons are three nuceotideslong

Answer 42

A) the degeneracy of the genetic code

Question 43

To study deep divergences in the evolutionary
tree of life, you should use genes that: a) do not mutate
b) accumulate mutations slowly
c) accumulate mutations rapidly

Answer 43

B) accumulate mutations slowly

Question 44

What comes after the step show above?
(look at a picture, I couldn’t get it to paste in)
a) Translocation
b) Cleavage of the polypeptide from the tRNA c) Filling of the E site by an aminoacylatedtRNA d) Transfer of the polypeptide chain from the tRNA
in the A site to the tRNA in the P site

Answer 44

A) Translocation

Question 45

What makes a liver cell different from a pancreatic cell?

a) Different patterns of gene expression b) Different DNA sequences
c) Different genes d) All the above

Answer 45

A) different patterns of gene expression

Question 46

What would be the consequence if an aminoacyl tRNA synthetase was mutated so that it added an amino acid to more than one type of tRNA?

a) Protein synthesis would halt
b) Codons could not be properly read.
c) tRNAs would become unstable (they’d be degraded)
d) Proteins would contain incorrect amino acids e) Codons in mRNAs would be altered

Answer 46

D) proteins would contain incorrect amino acids

Question 47

Which of the following is a protein? a) a promoter

b) a transcription factor
c) a codon

Answer 47

B) a transcription factor

Question 48

Which of the following is the largest?

a) a histone
b) a nucleosome
c) a deoxynucleotide

Answer 48

B) a nucleosome

Question 49

A woman who is a carrier for colorblindness has a daughter with a man who has normal color vision. The daugher is colorblind and is aneuploid with only one X chromosome (and no Y chromosome). The daugher’s aneuploidy must be due to:

a) nondisjunction in the mother
b) nondisjunction in the father
c) nondisjunction in either the father or mother

Answer 49

B) nondisjunction in the father