TEST BANK For Karp’s Cell and Molecular Biology, 9th
Edition by Gerald Karp, Janet Iwasa
1. The eukaryotic cell cycle is composed of four phases in the following order:
a. G1; S; G2; M
b. G1; G2; S; M
c. G1; M; G2; S
d. S; G1; G2; M - ANSWER:G1; S; G2; M
2. The length of time it takes for the cells labeled during DNA synthesis to begin to
enter mitosis is a good estimate of the length of the _______ phase(s).
a. G1
b. S
c. G2
d. M - ANSWER:G2
3. In a typical cycling mammalian cell, _______ of the cell cycle is spent in
interphase.
a. 99%
b. 95%
c. 75%
d. 50% - ANSWER:95%
4. Cell cycles of early embryonic animal cells are unusual because they have
a. no G1 or G2.
b. an elongated G1 and G2.
c. a short S.
d. a much shortened M. - ANSWER:no G1 or G2
5. The number of cells in the different phases of a population can be determined
most easily by using a(n) _______ to measure the amount of DNA per cell in a large
sample of cells.
a. scintillation counter
b. flow cytometer
c. fluorescence microscope
d. phase-contrast microscope after autoradiography - ANSWER:flow cytometer
6. Cells in the quiescent phase of the cell cycle are said to be in the _______ phase.
a. G0
b. G1
c. G2
d. M - ANSWER:G0
,7. Which of the following represents the amount of DNA in a typical G2 cell?
a. n
b. 2n
c. 4n
d. 8n - ANSWER:4n
8. The G1 checkpoint in budding yeast cells is called
a. START.
b. the restriction point.
c. the decision point.
d. the G1/S boundary. - ANSWER:START
9. The G1 checkpoint in animal cells is called
a. START.
b. the restriction point.
c. the decision point.
d. the G1/S boundary. - ANSWER:the restriction point
10. Skin fibroblasts arrested in G0 are stimulated near a wound to enter G1 by
_______ growth factor.
a. epidermal
b. fibroblast
c. platelet-derived
d. keratinocyte - ANSWER:platelet-derived
11. The G2 checkpoint prevents entry into _______ if _______.
a. G1; DNA synthesis is not complete and/or DNA is damaged
b. S; DNA synthesis is not complete and/or DNA is damaged
c. G2; DNA synthesis is not complete and/or DNA is damaged
d. M; DNA synthesis is not complete and/or DNA is damaged - ANSWER:M; DNA
synthesis is not complete and/or DNA is damaged
12. Maturation promotion factor (MPF), discovered by Masui and Markert, is the
factor that
a. is missing in the cdc2 mutant in yeast.
b. induces entry into meiosis when injected into frog oocytes.
c. fluctuates in amount during early cleavages of sea urchin eggs.
d. fluctuates in amount during the cell cycle of mammalian cells - ANSWER:induces
entry into meiosis when injected into frog oocytes.
13. MPF is a
a. monomeric protein kinase.
b. dimer of two molecules of Cdk1.
c. dimer of Cdk1 and cyclin A.
d. dimer of Cdk1 and cyclin B. - ANSWER:dimer of Cdk1 and cyclin B.
, 14. MPF is a general regulator of the transition from
a. G1 to S.
b. S to G2.
c. G2 to M.
d. metaphase to anaphase. - ANSWER:G2 to M
15. Studies on cell cycle mutants in budding and fission yeasts demonstrated that
cdc2 and cdc28 both encode a
a. protein kinase.
b. protein phosphatase.
c. ubiquinating enzyme.
d. growth factor. - ANSWER:protein kinase
16. Two sea urchin proteins were named cyclin A and B because, during the
embryonic cell cycle, they were periodically
a. activated and inactivated by phosphorylation and dephosphorylation.
b. synthesized and degraded.
c. bound and released by another protein.
d. ubiquitylated and non-ubiquitylated. - ANSWER:synthesized and degraded
17. To become active, Cdk1 must
a. bind cyclin.
b. bind cyclin and be phosphorylated on tyrosine 15 and threonines 14 and 161.
c. bind cyclin and be phosphorylated on tyrosine 15, and be dephosphorylated on
threonines 14 and 161.
d. bind cyclin and be phosphorylated on threonine 161, and be dephosphorylated on
threonine 14 and tyrosine 15. - ANSWER:bind cyclin and be phosphorylated on
tyrosine 15 and threonines 14 and 161
18. Cdks bind to cyclin and are activated by
a. phosphorylation by Wee1.
b. dephosphorylation by Cdc25 protein phosphatase.
c. the binding of Ink4.
d. the binding of Cip. - ANSWER:phosphorylation by Wee1
19. Which cyclin(s) is/are required to pass the G1 restriction point in animal cells?
a. Cyclin A
b. Cyclin A and Cyclin B
c. Cyclin D
d. Cyclin D and Cyclin E - ANSWER:Cyclin D
20. Passage of animal cells through the cell cycle is regulated primarily by
a. the availability of nutrients.
b. intracellular second messengers.
c. extracellular growth factors.
d. direct cell surface interactions. - ANSWER:extracellular growth factors
Edition by Gerald Karp, Janet Iwasa
1. The eukaryotic cell cycle is composed of four phases in the following order:
a. G1; S; G2; M
b. G1; G2; S; M
c. G1; M; G2; S
d. S; G1; G2; M - ANSWER:G1; S; G2; M
2. The length of time it takes for the cells labeled during DNA synthesis to begin to
enter mitosis is a good estimate of the length of the _______ phase(s).
a. G1
b. S
c. G2
d. M - ANSWER:G2
3. In a typical cycling mammalian cell, _______ of the cell cycle is spent in
interphase.
a. 99%
b. 95%
c. 75%
d. 50% - ANSWER:95%
4. Cell cycles of early embryonic animal cells are unusual because they have
a. no G1 or G2.
b. an elongated G1 and G2.
c. a short S.
d. a much shortened M. - ANSWER:no G1 or G2
5. The number of cells in the different phases of a population can be determined
most easily by using a(n) _______ to measure the amount of DNA per cell in a large
sample of cells.
a. scintillation counter
b. flow cytometer
c. fluorescence microscope
d. phase-contrast microscope after autoradiography - ANSWER:flow cytometer
6. Cells in the quiescent phase of the cell cycle are said to be in the _______ phase.
a. G0
b. G1
c. G2
d. M - ANSWER:G0
,7. Which of the following represents the amount of DNA in a typical G2 cell?
a. n
b. 2n
c. 4n
d. 8n - ANSWER:4n
8. The G1 checkpoint in budding yeast cells is called
a. START.
b. the restriction point.
c. the decision point.
d. the G1/S boundary. - ANSWER:START
9. The G1 checkpoint in animal cells is called
a. START.
b. the restriction point.
c. the decision point.
d. the G1/S boundary. - ANSWER:the restriction point
10. Skin fibroblasts arrested in G0 are stimulated near a wound to enter G1 by
_______ growth factor.
a. epidermal
b. fibroblast
c. platelet-derived
d. keratinocyte - ANSWER:platelet-derived
11. The G2 checkpoint prevents entry into _______ if _______.
a. G1; DNA synthesis is not complete and/or DNA is damaged
b. S; DNA synthesis is not complete and/or DNA is damaged
c. G2; DNA synthesis is not complete and/or DNA is damaged
d. M; DNA synthesis is not complete and/or DNA is damaged - ANSWER:M; DNA
synthesis is not complete and/or DNA is damaged
12. Maturation promotion factor (MPF), discovered by Masui and Markert, is the
factor that
a. is missing in the cdc2 mutant in yeast.
b. induces entry into meiosis when injected into frog oocytes.
c. fluctuates in amount during early cleavages of sea urchin eggs.
d. fluctuates in amount during the cell cycle of mammalian cells - ANSWER:induces
entry into meiosis when injected into frog oocytes.
13. MPF is a
a. monomeric protein kinase.
b. dimer of two molecules of Cdk1.
c. dimer of Cdk1 and cyclin A.
d. dimer of Cdk1 and cyclin B. - ANSWER:dimer of Cdk1 and cyclin B.
, 14. MPF is a general regulator of the transition from
a. G1 to S.
b. S to G2.
c. G2 to M.
d. metaphase to anaphase. - ANSWER:G2 to M
15. Studies on cell cycle mutants in budding and fission yeasts demonstrated that
cdc2 and cdc28 both encode a
a. protein kinase.
b. protein phosphatase.
c. ubiquinating enzyme.
d. growth factor. - ANSWER:protein kinase
16. Two sea urchin proteins were named cyclin A and B because, during the
embryonic cell cycle, they were periodically
a. activated and inactivated by phosphorylation and dephosphorylation.
b. synthesized and degraded.
c. bound and released by another protein.
d. ubiquitylated and non-ubiquitylated. - ANSWER:synthesized and degraded
17. To become active, Cdk1 must
a. bind cyclin.
b. bind cyclin and be phosphorylated on tyrosine 15 and threonines 14 and 161.
c. bind cyclin and be phosphorylated on tyrosine 15, and be dephosphorylated on
threonines 14 and 161.
d. bind cyclin and be phosphorylated on threonine 161, and be dephosphorylated on
threonine 14 and tyrosine 15. - ANSWER:bind cyclin and be phosphorylated on
tyrosine 15 and threonines 14 and 161
18. Cdks bind to cyclin and are activated by
a. phosphorylation by Wee1.
b. dephosphorylation by Cdc25 protein phosphatase.
c. the binding of Ink4.
d. the binding of Cip. - ANSWER:phosphorylation by Wee1
19. Which cyclin(s) is/are required to pass the G1 restriction point in animal cells?
a. Cyclin A
b. Cyclin A and Cyclin B
c. Cyclin D
d. Cyclin D and Cyclin E - ANSWER:Cyclin D
20. Passage of animal cells through the cell cycle is regulated primarily by
a. the availability of nutrients.
b. intracellular second messengers.
c. extracellular growth factors.
d. direct cell surface interactions. - ANSWER:extracellular growth factors
