Question 1

Which of the following best describes the role of the centromere during mitosis?

Accepted Answer

It is the site where spindle fibers attach to separate sister chromatids during anaphase.

Question 2

During which phase of the cell cycle does DNA replication occur, and what is the result of this process?

Accepted Answer

S phase; each chromosome consists of two sister chromatids.

Question 3

A scientist observes a cell with chromosomes aligned at the center of the cell, attached to spindle fibers from opposite poles. Which phase is this cell in?

Accepted Answer

Metaphase

Question 4

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 5

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

Accepted Answer

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

Question 6

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

Accepted Answer

M checkpoint

Question 7

A mutation in which gene is most likely to result in the loss of cell cycle arrest in response to DNA damage?

Accepted Answer

p53

Question 8

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

Accepted Answer

They have mutations that disrupt normal cell cycle control mechanisms.

Question 9

Which of the following is a function of tumor-suppressor proteins?

Accepted Answer

Repair damaged DNA

Question 10

A cell is observed to have condensed chromosomes, a disassembled nuclear envelope, and spindle fibers attaching to kinetochores. Which phase is this?

Accepted Answer

Prometaphase

Question 11

Which of the following best describes the process of binary fission in bacteria?

Accepted Answer

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

Question 12

Which of the following statements about cyclin-dependent kinases (Cdks) is correct?

Accepted Answer

Cdks are only active when bound to a cyclin.

Question 13

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

Accepted Answer

Increased predisposition to certain cancers

Question 14

Which of the following is a key event that occurs during anaphase of mitosis?

Accepted Answer

Sister chromatids are separated and pulled toward opposite poles.

Question 15

Which of the following best explains the difference between proto-oncogenes and oncogenes?

Accepted Answer

Proto-oncogenes are normal genes that can become oncogenes when mutated.

Question 16

Which of the following is a real-world example of the importance of the G1 checkpoint?

Accepted Answer

A skin cell with damaged DNA is prevented from dividing, reducing the risk of skin cancer.

Question 17

Which of the following best describes the function of the mitotic spindle during cell division?

Accepted Answer

It organizes and separates chromosomes during mitosis.

Question 18

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

Accepted Answer

Gene amplification, point mutation, or translocation

Question 19

Which of the following best explains why the incidence of cancer increases with age?

Accepted Answer

Multiple mutations accumulate over time, increasing the likelihood of cancer.

The Cell Cycle and Molecular Biology of Cancer: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard