Question 1

A cell that is terminally differentiated will

Accepted Answer

A) replicate its DNA. 
B) reenter the cell cycle only once a year. 
C) dismantle the cell-cycle control system. 
D) arrest after S phase. 
A) replicate its DNA. 
B) reenter the cell cycle only once a year. 
C) dismantle the cell-cycle control system. 
D) arrest after S phase.

Question 2

You have isolated a strain of mutant yeast cells that divides normally at 30°C but cannot enter M phase at 37°C.You have isolated its mitotic cyclin and mitotic Cdk and find that both proteins are produced and can form a normal M-Cdk complex at both temperatures.Which of the following temperature-sensitive mutations could NOT be responsible for the behavior of this strain of yeast?

Accepted Answer

A) inactivation of a protein kinase that acts on the mitotic Cdk kinase 
B) inactivation of an enzyme that ubiquitylates M cyclin 
C) inactivation of a phosphatase that acts on the mitotic Cdk kinase 
D) a decrease in the levels of a transcriptional regulator required for producing sufficient amounts of M cyclin 
A) inactivation of a protein kinase that acts on the mitotic Cdk kinase 
B) inactivation of an enzyme that ubiquitylates M cyclin 
C) inactivation of a phosphatase that acts on the mitotic Cdk kinase 
D) a decrease in the levels of a transcriptional regulator required for producing sufficient amounts of M cyclin

Question 3

MPF activity was discovered when cytoplasm from a Xenopus M-phase cell was injected into Xenopus oocytes, inducing the oocytes to form a mitotic spindle.In a control experiment, Xenopus interphase cytoplasm was injected into oocytes and shown not to induce the formation of a mitotic spindle.Which of the following statements is NOT a legitimate conclusion from the control experiment?

Accepted Answer

A) The piercing of the oocyte membrane by a needle is insufficient to cause mitotic spindle formation. 
B) An increased volume of cytoplasm is insufficient to cause mitotic spindle formation. 
C) Injection of extra RNA molecules is insufficient to cause mitotic spindle formation. 
D) Components of an interphase nucleus are insufficient to cause mitotic spindle formation. 
A) The piercing of the oocyte membrane by a needle is insufficient to cause mitotic spindle formation. 
B) An increased volume of cytoplasm is insufficient to cause mitotic spindle formation. 
C) Injection of extra RNA molecules is insufficient to cause mitotic spindle formation. 
D) Components of an interphase nucleus are insufficient to cause mitotic spindle formation.

Question 4

For each of the following sentences, fill in the blanks with the best word or phrase selected from the list below.Not all words or phrases will be used; each word or phrase may be used once.
$\begin{array}{lll}
\text { assemble } & \mathrm{G}_{1} & \text { phosphorylation } \
\text { condense } & \mathrm{G}_{2} & \text { polymerization } \
\text { cytokinesis } & \mathrm{M} & \mathrm{S} \
\text { degrade } & \text { replicate } & \text { segregate }
\end{array}$

A cell contains the most DNA after __________ phase of the cell cycle, the period when a cell __________s its DNA.A cell is smallest in size after __________ phase of the cell cycle, which includes __________, the process by which the cytoplasm is cleaved in two.S and M phases are separated by gap phases, with the first one called the __________ phase and the second one, which follows S phase, called the __________ phase of the cell cycle.During mitosis, the mitotic spindle is built to __________ chromosomes.

Accepted Answer

A cell contains the most DNA after S pha

Question 5

Which of the following statements is FALSE?

Accepted Answer

A) DNA synthesis begins at origins of replication. 
B) The loading of the origin recognition complexes (ORCs) is triggered by S-Cdk. 
C) The phosphorylation and degradation of Cdc6 help to ensure that DNA is replicated only once in each cell cycle. 
D) DNA synthesis can only begin after prereplicative complexes assemble on the ORCs. 
A) DNA synthesis begins at origins of replication. 
B) The loading of the origin recognition complexes (ORCs) is triggered by S-Cdk. 
C) The phosphorylation and degradation of Cdc6 help to ensure that DNA is replicated only once in each cell cycle. 
D) DNA synthesis can only begin after prereplicative complexes assemble on the ORCs.

Question 6

Condensins

Accepted Answer

A) are degraded when cells enter M phase. 
B) assemble into complexes on the DNA when phosphorylated by M-Cdk. 
C) are involved in holding sister chromatids together. 
D) bind to DNA before DNA replication begins. 
A) are degraded when cells enter M phase. 
B) assemble into complexes on the DNA when phosphorylated by M-Cdk. 
C) are involved in holding sister chromatids together. 
D) bind to DNA before DNA replication begins.

Question 7

At the end of DNA replication, the sister chromatids are held together by the

Accepted Answer

A) kinetochores. 
B) securins. 
C) cohesins. 
D) histones. 
A) kinetochores. 
B) securins. 
C) cohesins. 
D) histones.

A cell that is terminally differentiated will

Which of the following statements is FALSE?

Condensins

At the end of DNA replication, the sister chromatids are held together by the

Cells: The Fundamental Units of Life

Chemical Components of Cells

Energy, Catalysis, and Biosynthesis

Protein Structure and Function

DNA and Chromosomes

DNA Replication and Repair

From DNA to Protein

Control of Gene Expression

How Genes and Genomes Evolve

Analyzing the Structure and Function of Genes

Membrane Structure

Transport Across Cell Membranes

How Cells Obtain Energy From Food

Energy Generation in Mitochondria and Chloroplasts

Intracellular Compartments and Protein Transport

Cell Signaling

Cytoskeleton

Sexual Reproduction and the Power of Genetics

Cell Communities: Tissues, Stem Cells, and Cancer

Filters

Exam 18: The Cell-Division Cycle

A cell that is terminally differentiated will

Which of the following statements is FALSE?

Condensins

At the end of DNA replication, the sister chromatids are held together by the

Cells: The Fundamental Units of Life

Chemical Components of Cells

Energy, Catalysis, and Biosynthesis

Protein Structure and Function

DNA and Chromosomes

DNA Replication and Repair

From DNA to Protein

Control of Gene Expression

How Genes and Genomes Evolve

Analyzing the Structure and Function of Genes

Membrane Structure

Transport Across Cell Membranes

How Cells Obtain Energy From Food

Energy Generation in Mitochondria and Chloroplasts

Intracellular Compartments and Protein Transport

Cell Signaling

Cytoskeleton

Sexual Reproduction and the Power of Genetics

Cell Communities: Tissues, Stem Cells, and Cancer

Filters