Question 1

Which phase of the cell cycle is primarily responsible for DNA replication, and what is the main event that occurs during this phase?

Accepted Answer

S phase; DNA is duplicated

Question 2

During which phase of the cell cycle does the cell spend the majority of its time, and what is the main activity during this phase?

Accepted Answer

Interphase; cell growth and DNA replication

Question 3

What is the correct sequence of events in the cell cycle for a cell that is actively dividing?

Accepted Answer

G1 → S → G2 → Mitotic phase

Question 4

Which of the following best describes the G0 phase?

Accepted Answer

A non-dividing, non-growing state for many cell types

Question 5

If a human cell has just completed the S phase, how many chromosomes are present in the nucleus?

Accepted Answer

46 chromosomes, each with two sister chromatids

Question 6

Which protein complex is responsible for compacting DNA into chromatin during interphase?

Accepted Answer

Histones

Question 7

A mutation prevents the formation of centromeres during the cell cycle. What is the most likely consequence during mitosis?

Accepted Answer

Sister chromatids will not be held together

Question 8

Which of the following statements about genes is correct?

Accepted Answer

Genes are short segments of DNA that code for proteins

Question 9

A scientist observes a cell with visible chromosomes aligned in the center of the cell. Which phase is this cell most likely in?

Accepted Answer

Mitotic phase

Question 10

Which of the following equations correctly represents the number of base pairs in the human genome?

Accepted Answer

$$3 	imes 10^9$

Question 11

If a cell fails to complete the G2 phase, which of the following is most likely to occur?

Accepted Answer

The cell will not properly prepare for mitosis

Question 12

Which of the following best describes the relationship between chromatin and chromosomes?

Accepted Answer

Chromatin is condensed into chromosomes during mitosis

Question 13

A patient has a genetic disorder affecting histone production. Which cellular process would be most directly impacted?

Accepted Answer

DNA packaging into chromatin

Question 14

Which of the following is true regarding the number of chromosomes in different species?

Accepted Answer

The number of chromosomes varies by species

Question 15

Which phase of the cell cycle is characterized by the cell preparing for division and continuing to grow slowly?

Accepted Answer

G2 phase

Question 16

If a neuron enters the G0 phase after adolescence, what does this imply about its ability to divide?

Accepted Answer

It will remain in a non-dividing state permanently

Question 17

Which of the following best explains why DNA must be duplicated before cell division?

Accepted Answer

To ensure each new cell receives a complete set of genetic information

Question 18

A cell is observed to have double the normal amount of DNA but has not yet divided. In which phase is this cell most likely found?

Accepted Answer

G2 phase

Question 19

Which of the following statements about the mitotic phase is correct?

Accepted Answer

It includes both mitosis and cytokinesis

Question 20

Which of the following best describes a gene?

Accepted Answer

A segment of DNA that codes for one or more proteins

The Cell Cycle and DNA Structure: Study Notes for Human Biology

Study Guide - Practice Questions