Question 1

If a cell stops at the G1 checkpoint,this is most likely due to what problem?
A)The DNA has not finished replicating.
B)The chromosomes are not aligned properly.
C)There is DNA damage.
D)The cell is cancerous.
E)There is no problem.The cell normally stops at the G1 checkpoint.

Accepted Answer

The G1 checkpoint is responsible for ensuring that the DNA is undamaged and suitable for replication. If there is DNA damage present, the cell will stop at this checkpoint to allow for repair before continuing with the cell cycle.

Question 2

Which of the following is the correct sequence for the cell cycle? A)S-M-G₁-G₂ B)S-M-G₂-G₁ C)S-G₁-G₁-M D)S-G₂-M-G₁ E)S-G₁-M-G₂

Accepted Answer

The correct sequence for the cell cycle is S (Synthesis phase) - G2 (Gap 2 phase) - M (Mitosis) - G1 (Gap 1 phase).

Question 3

The only function of apoptosis is to destroy healthy cells when they become damaged or infected.

Accepted Answer

Apoptosis or programmed cell death has multiple functions in the human body, including eliminating damaged or infected cells, controlling cell proliferation, and maintaining tissue homeostasis.

Question 4

Growth factors that are transported through the blood play what role in the cell cycle?
A)an internal signal that tells the cell to stop dividing and repair its DNA
B)an internal signal that functions as an executioner
C)an internal signal to tell the cell which stage of the cell cycle to enter next
D)an external signal to tell the cell how long it should spend in each phase of the cell cycle
E)an external signal to tell the cell whether or not to divide

Accepted Answer

Growth factors that are transported through the blood act as external signals to tell the cell whether to divide or not. They bind to receptors on the cell surface and trigger intracellular signaling pathways that ultimately result in the activation of cell growth and division. Some growth factors also promote survival and differentiation of cells. However, they do not play a direct role in regulating the different stages of the cell cycle or repairing DNA damage.

Question 5

Which of the following is not true concerning the checkpoints in the cell cycle?
A)Mitosis stops if chromosomes are not properly aligned.
B)Mitosis will not occur if DNA is damaged or not replicated.
C)If DNA is damaged,apoptosis may occur.
D)The first checkpoint is located in the S phase of interphase.
E)Cyclins must be present at certain stages to advance to the next stage.

Accepted Answer

The first checkpoint is actually located in the G1 phase of interphase, not the S phase. The G1 checkpoint checks for cell size, nutrient availability, and DNA damage before allowing the cell to proceed to the S phase where DNA replication occurs.

Question 6

Upon examination,a cell is found to have twice as much DNA as the normal diploid state but is no longer in the process of replicating the DNA.All of the DNA is found within a single nucleus.Which stage of the cell cycle is this cell in?
A)M phase
B)S phase
C)G1 phase
D)G2 phase
E)cytokinesis

Accepted Answer

The cell is not in S phase as it is not actively replicating its DNA. It cannot be in M phase or cytokinesis as it only has one nucleus, and those stages involve the division of the nucleus or cell. Therefore, the cell must be in G2 phase, which is the stage where the cell prepares for mitosis after the completion of DNA replication. The cell has twice as much DNA as the normal diploid state because it has already replicated its DNA in the S phase, but has not yet entered M phase.

Question 7

Which type of genes,when abnormally activated so that protein is always present and active,can result in cancer?
A)tumor suppressor genes
B)initator caspase genes
C)proto-oncogenes
D)DNA repair protein genes
E)executioner caspase genes

Accepted Answer

Proto-oncogenes, when abnormally activated or mutated, can become oncogenes, which promote constant protein production and activity, leading to uncontrolled cell growth and potentially resulting in cancer.

Question 8

Which is NOT a correct association? A)S stage-DNA synthesis B)M stage-mitosis and cytokinesis C)interphase-shortest stage of the cell cycle D)G₁ stage-cell grows in size and cell organelles increase in number E)G₂ stage-metabolic preparation for mitosis

Accepted Answer

Interphase is actually the longest stage of the cell cycle, not the shortest.

Question 9

Which of the following best characterizes apoptosis?
A)Apoptosis is bad for an organism.
B)The stages of apoptosis are different in each cell type.
C)Apoptosis happens accidentally to healthy cells.
D)Apoptosis plays a normal role in development and cancer prevention.
E)Apoptosis results in our going from a fertilized egg to trillions of cells.

Accepted Answer

Apoptosis plays a normal role in development and cancer prevention. Apoptosis is a programmed cell death that plays an important role in development, tissue homeostasis, and cancer prevention. It is a natural process that helps eliminate unwanted or damaged cells and is crucial for maintaining the health of an organism.

Question 10

Technically,mitosis refers to nuclear division and NOT cytoplasmic division.

Accepted Answer

Mitosis specifically refers to the division of the cell nucleus into two identical nuclei. The division of the cytoplasm, known as cytokinesis, follows mitosis and is a separate process.

Question 11

Following a cut or scrape,which process repairs your skin?
A)meiosis
B)meiosis and mitosis
C)mitosis
D)mitosis and apoptosis
E)apoptosis

Accepted Answer

Mitosis is the process of cell division that repairs and replaces damaged cells in the body. Therefore, after a cut or scrape, mitosis is the process that repairs the skin. Meiosis is a type of cell division that produces gametes for sexual reproduction and is not involved in repairing skin. Apoptosis is programmed cell death, which is not relevant to repairing skin.

Question 12

The mitotic stage of cell division consists of
A)DNA synthesis and DNA degradation.
B)mitosis and cytokinesis.
C)duplication and division.
D)cell growth and cell death.
E)meiosis and mitosis.

Accepted Answer

The mitotic stage of cell division consists of two main events: mitosis, which is the division of the nucleus, and cytokinesis, which is the division of the cytoplasm. During mitosis, the duplicated chromosomes align and separate into two identical daughter nuclei. Cytokinesis then completes the process by dividing the cell into two separate daughter cells. Choices A, C, D, and E are incorrect as they either include unrelated processes or refer to the stages of meiosis, which is a different type of cell division.

Question 13

There are two sets of caspases operating during apoptosis.Which of the following statements does not correctly characterize the role of these caspases?
A)One set of caspases are called initators because they receive a signal to activate the second set.
B)One set of capsases are called executioners because they dismantle the cell.
C)Caspases can be unleashed by either internal or external signals.
D)Caspases are normally active during the entire cell cycle.
E)Caspases are responsible for the typical stages a cell goes through during apoptosis.

Accepted Answer

Caspases are not normally active during the entire cell cycle. They are only activated during apoptosis, which is a programmed cell death process.

Question 14

Which of the following proteins would you expect to be a coded for by a proto-oncogene?
A)a growth factor receptor
B)a DNA repair protein
C)a protein involved with the G1 checkpoint
D)a caspase
E)a DNA replication protein

Accepted Answer

Proto-oncogenes code for proteins that promote cell growth, division, and survival. Therefore, a growth factor receptor, which plays a role in promoting cell growth and division, would likely be coded for by a proto-oncogene. DNA repair proteins, checkpoint proteins, and caspases, on the other hand, play roles in preventing cell growth and promoting apoptosis, and therefore would not be expected to be coded for by proto-oncogenes. DNA replication proteins are necessary for cell growth and division, but not necessarily oncogenic in nature.

Question 15

During which stage of the cell cycle do the chromosomes duplicate?
A)prophase
B)anaphase
C)interphase
D)telophase
E)mitosis

Accepted Answer

Chromosomes duplicate during the interphase stage of the cell cycle, specifically during the S phase (synthesis phase). This is before mitosis occurs, which includes the stages of prophase, metaphase, anaphase, and telophase.

Question 16

Which of the following is not involved in the regulation of the cell cycle?
A)cyclins
B)internal and external signals
C)growth factors
D)checkpoints
E)caspases

Accepted Answer

Caspases are involved in programmed cell death (apoptosis) and are not directly involved in the regulation of the cell cycle.

Question 17

During interphase,
A)the cell begins to die.
B)the cell rounds up and detaches from its neighbors.
C)two nuclei split.
D)the cell is at rest.
E)hereditary material duplicates itself.

Accepted Answer

During interphase, the cell is in a state of growth and metabolism. One major event that occurs during interphase is the duplication of the cell's hereditary material (DNA) in preparation for cell division. The other options listed are not accurate descriptions of interphase.

Question 18

Which of the following descriptions does not occur during apoptosis?
A)cell rounds up
B)cells lose contact with neighbors
C)nucleus fragments
D)DNA is duplicated
E)plasma membrane develops blisters

Accepted Answer

DNA being duplicated is a characteristic of cell division, not apoptosis. During apoptosis, the cell will round up, lose contact with neighbors, the nucleus will fragment, and the plasma membrane may develop blisters.

Question 19

The cell cycle consists of
A)mitosis and interphase.
B)meiosis and interphase.
C)prophase and interphase.
D)metaphase and interphase.
E)changes from a haploid to a diploid state.

Accepted Answer

The cell cycle consists of two main phases: interphase, which involves growth and DNA replication, and mitosis, which involves cell division. Meiosis is a separate type of cell division that occurs only in certain cells to produce haploid gametes. Prophase and metaphase are specific stages within the mitotic phase of the cell cycle. The cell cycle does not involve changes from haploid to diploid states.

Question 20

When does apoptosis occur?
A)during development
B)during interphase
C)during mitosis
D)during meiosis
E)during injury repair

Accepted Answer

Apoptosis is programmed cell death and occurs during development to ensure proper formation of tissues and organs.

Quiz 5: Cell Division

If a cell stops at the G1 checkpoint,this is most likely due to what problem?

Which of the following is the correct sequence for the cell cycle?

The only function of apoptosis is to destroy healthy cells when they become damaged or infected.

Growth factors that are transported through the blood play what role in the cell cycle?

Which of the following is not true concerning the checkpoints in the cell cycle?

Upon examination,a cell is found to have twice as much DNA as the normal diploid state but is no longer in the process of replicating the DNA.All of the DNA is found within a single nucleus.Which stage of the cell cycle is this cell in?

Which type of genes,when abnormally activated so that protein is always present and active,can result in cancer?

Which is NOT a correct association?

Which of the following best characterizes apoptosis?

Technically,mitosis refers to nuclear division and NOT cytoplasmic division.

Following a cut or scrape,which process repairs your skin?

The mitotic stage of cell division consists of

There are two sets of caspases operating during apoptosis.Which of the following statements does not correctly characterize the role of these caspases?

Which of the following proteins would you expect to be a coded for by a proto-oncogene?

During which stage of the cell cycle do the chromosomes duplicate?

Which of the following is not involved in the regulation of the cell cycle?

During interphase,

Which of the following descriptions does not occur during apoptosis?

The cell cycle consists of

When does apoptosis occur?