Download 1) S phase in the cell cycle is

1) S phase in the cell cycle is
a. after G2
b. when DNA synthesis occurs
c. directly before interphase
d. when the cell divides
e. characterized by growth of the cell
2) The microtubules play an important role in mitosis. Choose the correct process that they
are involved in:
a. formation of cleavage furrow
b. disassembly of the nuclear membrane
c. formation of the sister chromatids
d. separation of sister chromatids
e. pairing of sister chromatids
3) A mule is the offspring of a male donkey (donkey somatic cells contain 62
chromosomes) and a female horse (horse somatic cells contain 64 chromosomes) and is
sterile. Which of the following is FALSE?
a. The horse egg had 32 chromosomes
b. The donkey sperm had 31 chromosomes
c. Mule zygote has 63 chromosomes
d. Mule cells complete mitosis
e. Mule cells complete meiosis
4) Which one of the following occurs in meiosis, but not mitosis?
a. A spindle apparatus forms.
b. Homologous chromosomes form pairs.
c. The nuclear envelope disappears.
d. The cells formed have the same combination of genes as found in the initial cell.
e. Sister chromatids are separated
5) A rat exhibits the dominant phenotype of normal hearing. The genotype of this rat:
a. cannot be determined without molecular analysis of its DNA
b. is homozygous for the dominant allele
c. is heterozygous for the dominant allele
d. can be determined by a test cross to a rat that is phenotypically recessive
e. can be determined by a test cross to a rat that is phenotypically dominant
6) Color blindness is a sex-linked trait. If a female who is a carrier for colorblindness mates
with a male who is colorblind, which of the following is TRUE?
a. There is no chance that any of the children will be colorblind
b. The sons have a 100% chance of being colorblind
c. The sons have a 50% chance of being colorblind
d. The sons have a 25% chance of being colorblind
e. The sons will all be carriers
7) In the Hershey and Chase experiment if phage grown in radioactive sulfur were used to
infect a culture of bacteria. Which of the following could be TRUE?
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a. After growth bacteria contained radioactively labeled phage
b. Phage DNA was radioactive
c. Bacterial proteins were radioactive
d. Bacteria contained both radioactive DNA and radioactive proteins
e. Phage coat proteins were radioactive
8). Starting with a fertilized egg (zygote), how many cell divisions would produce an early
embryo with 128 cells?
a. 6
b. 7
c. 16
d. 32
e. 64
9). Independent assortment of chromosomes is a result of
a. the random and independent way in which each pair of homologous chromosomes lines
up at the metaphase plate during meiosis I.
b. the random nature of the fertilization of ova by sperm.
c. the random distribution of the sister chromatids to the two daughter cells during
anaphase II.
d. the relatively small degree of homology shared by the X and Y chromosomes.
e. All of the above
10). How many different combinations of maternal and paternal chromosomes can be
packaged in gametes made by an organism with a diploid number of 8 (2n = 8)?
a. 2
b. 4
c. 8
d. 16
e. 32
11) Assuming independent assortment of all gene pairs, what is the probability that parents
of the following genotypes AABbCc X AaBbCc will produce offsprings of AAbbCC?
a. 1/8
b. 1/128
c. 1/64
d. 1/32
e. 1/16
12). Vincristine is a chemotherapy drug used to treat cancer. It interferes with the assembly
of microtubules. If you observe dividing cells that have been applied with vincristine you will
most likely find that:
a. Cells are arrested in Telophase
b. The nuclear envelope is intact in all cells
c. The DNA has not condensed.
d. Cell division is taking place, but at a slower pace.
e. Condensed chromosomes are not aligned properly along metaphase plate.
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13) After mixing a heat-killed, infectious strain of bacteria with a living non-infectious strain,
you discover that some of the living cells are now infectious. Which observations would
provide the best evidence that the ability to infect is a HERITABLE trait?
a. DNA is passed from the heat-killed strain to the living strain.
b. Protein is passed from the heat-killed strain to the living strain.
c. The infectivity in the living strain is especially virulent.
d. Descendants of the living cells are also infectious.
e. Both DNA and protein passed from the heat-killed strain to the living strain.
14) In analysis of the nucleotide composition of DNA, which of the following will be found?
a.
b.
c.
d.
e.
2A = C + T
A = G and C = T
A/C = G/T
G+C=T+A
C/T = G/A
15) Shown below are three DNA substrates.
Suppose DNA polymerase and dNTPs are added to each of these substrates. For which of
them would new DNA synthesis occur?
a. Substrates 2 and 3, but not substrate 1.
b. All three substrates 1, 2 and 3.
c. Substrate 3 only.
d. Substrate 2 only.
e. Substrates 1 and 3, but not substrate 2.
16) Noted here are a few proteins whose functions are required for DNA replication:
I. Primase II. DNA ligase III. Helicase IV. DNA polymerase3 V. DNA polymerase1
Which of the following represents a correct sequence of their functions for “lagging strand”
DNA synthesis?
a. I, V, II, III
b. III, I, V, II, IV
c. III, I, IV, V, II
d. IV, I, V, II
e. I, III, IV, V
17) An Okazaki fragment has which of the following arrangements?
a. primase, polymerase, ligase
b. 3' RNA nucleotides, DNA nucleotides 5'
c. 5' RNA nucleotides, DNA nucleotides 3'
d. DNA polymerase I, DNA polymerase III
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e. 5' DNA to 3'
18) A wild-type looking fruitfly (gray body color and normal wings) has a genotype that is
heterozygous for yellow body color and short wings, is mated with a yellow fly with short
wings (homozygous recessive for both). The offsprings have the following phenotypic
distribution: wild-type=1556; yellow–short wings=1570; yellow-normal=316; gray-short
wings=324. The recombination frequency between yellow and short wings is:
a. 8.4%
b. 8.6%
c. 41.7%
d. 16.9%
e. 20.4%
19) The DNA double helix has a uniform diameter because ________, which have two
rings, always pair with ________, which have one ring.
a. purines; pyrimidines
b. pyrimidines; purines
c. deoxyribose sugars; ribose sugars
d. ribose sugars; deoxyribose sugars
e. nucleotides; nucleoside triphosphates
20) What kind of chemical bond is found between paired bases of the DNA double helix?
a. hydrogen
b. ionic
c. covalent
d. sulfhydryl
e. phosphate
21) What determines the nucleotide sequence of the newly synthesized strand during DNA
replication?
a. the particular DNA polymerase catalyzing the reaction
b. the relative amounts of the four nucleoside triphosphates in the cell
c. the nucleotide sequence of the template strand
d. the primase used in the reaction
e. both A and D
22) Which of the following best describes the addition of nucleotides to a growing DNA
chain?
a. A nucleoside triphosphate is added to the 5' end of the DNA, releasing a molecule of
pyrophosphate.
b. A nucleoside triphosphate is added to the 3' end of the DNA, releasing a molecule of
pyrophosphate.
c. A nucleoside diphosphate is added to the 5' end of the DNA, releasing a molecule of
phosphate.
d. A nucleoside diphosphate is added to the 3' end of the DNA, releasing a molecule of
phosphate.
e. A nucleoside monophosphate is added to the 3' end of the DNA.
23) What does transformation involve in bacteria?
a. the creation of a strand of DNA from an RNA molecule
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b. the creation of a strand of RNA from a DNA molecule
c. the infection of cells by a phage DNA molecule
d. the type of semiconservative replication shown by DNA
e. assimilation of external DNA into a cell
24) Which of the following DNA molecules will require the least amount of energy to
separate into a single strand from its complimentary strand.
a) 5’ ATATAATTGTAAGATA 3’
b) 5’ TATGAACTTTGACTTA 3’
c) 5’ GCATATTGGCACGTAA 3’
d) 5’ TGCAATGCATACCGTA 3’
e) 5’ GCATATTTTAAAATAG 3’
24) Which statement is NOT correct with regard to redox (oxidation-reduction) reactions:
a) a molecule is reduced if it loses electrons.
b) a molecule is oxidized if it loses electrons.
c) an electron donor is called a reducing agent.
d) an electron acceptor is called an oxidizing agent.
e) oxidation and reduction always go together.
25) Why does the oxidation of organic compounds by molecular oxygen to produce CO 2
and water release free energy:
a) The covalent bonds in organic molecules are higher energy bonds than those in water
and carbon dioxide.
b) Electrons are being moved from atoms that have a lower affinity for electrons (such as
C) to atoms with a higher affinity for electrons (such as O).
c) The oxidation of organic compounds can be used to make ATP.
d) The electrons have a higher potential energy when associated with water and CO2 than
they do in organic compounds.
e) The covalent bond in O2 is unstable and easily broken by electrons from organic
molecules.
26) The oxygen consumed during cellular respiration is involved directly in which of the
following:
a) glycolysis
b) the electron transport chain
c) the citric acid cycle
d) the oxidation of pyruvate to acetyl CoA
e) the phosphorylation of ADP to form ATP
27) Kreb’s cycle is often referred to as the “furnace of the cell” because:
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a) unlike the other metabolic pathways involved in cellular respiration that take place with a
negative free energy change, Kreb’s cycle takes place with a positive free energy change
b) most of the carbon of glucose is completely oxidized by the Kreb’s cycle
c) Kreb’s cycle produces most of the ATP formed during cellular respiration
d) it is a metabolic cycle where the first reactant is also the product of the cycle
e) entropy decreases during Kreb’s cycle
28) This reaction is the “net reaction” for which of the following:
10 [NADH + H+] + 2 FADH2 + 34 ADP + 34 Pi + 6 O2 → 10 NAD+ + 2 FAD+ + 34 ATP + 6
H2O
a)
b)
c)
d)
e)
the light reactions of photosynthesis
oxidative phosphorylation
Kreb’s cycle
electron transport/oxidative phosphorylation
glycolysis/fermentation
29) Which of the following are products of the light reactions of photosynthesis that are
utilized in the Calvin cycle:
a) CO2 and glucose
b) H2O and O2
c) ADP, Pi, and NADP+
d) electrons and H+
e) ATP and NADPH
30) What does cyclic electron flow in the chloroplast produce:
a) ATP
b) NADPH
c) glucose
d) a and b
e) a, b, and c
31) Assume that a thylakoid is somehow punctured so that the interior of the thylakoid is no
longer separated from the stroma. This damage will have the most direct effect on which of
the following:
a) the splitting of water
b) the absorption of light energy by chlorophyll
c) the flow of electrons from photosystem II to photosystem I
d) the synthesis of ATP
e) the reduction of NADP+
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32) Of the following, what do both mitochondria and chloroplasts have in common:
a) thylakoid membranes
b) chemiosmosis
c) ATP synthase
d) b and c only
e) a, b, and c
33) Which of the following sequences correctly represents the flow of electrons during
phtosynthesis:
a)
b)
c)
d)
e)
NADPH – O2 – CO2
H2O – NADPH – Calvin cycle
NADPH – chlorophyll – Calvin cycle
H2O – photosystem I – photosystem II
NADPH – electron transport chain – O2
34) Which of the following is the most energetically efficient biological energy
transformation:
a)
b)
c)
d)
e)
electron transport/oxidative phosphorylation
Kreb’s cycle
bioluminescence
glycolysis
photosynthesis
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