Question 1

Which of the following best describes the role of the mitotic spindle during mitosis?

Accepted Answer

It organizes and separates chromosomes by attaching to kinetochores and pulling sister chromatids apart.

Question 2

During which phase of the cell cycle does DNA replication occur?

Accepted Answer

S phase

Question 3

What is the main difference between cytokinesis in plant and animal cells?

Accepted Answer

Animal cells form a cleavage furrow, while plant cells form a cell plate.

Question 4

Which checkpoint in the cell cycle ensures that all chromosomes are properly attached to the spindle before anaphase begins?

Accepted Answer

M checkpoint

Question 5

A mutation in the p53 gene can lead to cancer because:

Accepted Answer

p53 normally repairs DNA damage and prevents the cell from passing on mutations.

Question 6

Which of the following equations correctly represents the change in chromosome number during mitosis in a human somatic cell?

Accepted Answer

$$2n \rightarrow 2n$$

Question 7

What is the function of cyclin-dependent kinases (Cdks) in the cell cycle?

Accepted Answer

They phosphorylate target proteins to regulate progression through the cell cycle.

Question 8

Which of the following best describes a proto-oncogene?

Accepted Answer

A gene that, when mutated, can become an oncogene and promote cancer.

Question 9

During which stage of mitosis do sister chromatids separate and move toward opposite poles?

Accepted Answer

Anaphase

Question 10

Which of the following is a real-life example of cell division for tissue renewal?

Accepted Answer

Healing of a skin wound after an injury

Question 11

What is the role of cohesin proteins during mitosis?

Accepted Answer

They hold sister chromatids together until anaphase.

Question 12

Which of the following best explains why cancer cells can divide uncontrollably?

Accepted Answer

They often have mutations in genes that regulate the cell cycle, such as proto-oncogenes and tumor suppressor genes.

Question 13

Which of the following is NOT a function of tumor-suppressor proteins?

Accepted Answer

Stimulating cell division

Question 14

A cell is observed to have condensed chromosomes aligned at the center of the cell, with spindle fibers attached to kinetochores. Which phase is this cell in?

Accepted Answer

Metaphase

Question 15

Which of the following best describes binary fission in bacteria?

Accepted Answer

The chromosome replicates and the cell divides into two genetically identical daughter cells.

Question 16

Which of the following is a correct sequence of events in the eukaryotic cell cycle?

Accepted Answer

G1 → S → G2 → M

Question 17

A patient inherits a mutant allele of the BRCA1 gene. What is the most likely consequence?

Accepted Answer

Increased risk of developing certain cancers, such as breast cancer

Question 18

Which of the following best explains why the G1 checkpoint is considered the most important in many cells?

Accepted Answer

It determines whether the cell will proceed with division or enter a nondividing state (G0).

Question 19

Which of the following is a direct result of the activity of maturation-promoting factor (MPF) at the G2 checkpoint?

Accepted Answer

Entry into the M phase (mitosis)

Question 20

Which of the following genetic changes can convert a proto-oncogene into an oncogene?

Accepted Answer

A mutation that increases the amount or activity of the protein product

The Cell Cycle and Molecular Biology of Cancer: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard