The Cell Cycle

Question 1

Most cell division results in what?

Answer 1

Genetically identical daughter cells

Question 2

What is the one characteristic that distinguishes living things from nonliving matter?

Answer 2

The ability of organisms to produce more of their own kind

Question 3

The continuity of life is based on ____ _____

Answer 3

Cell division

Question 4

All the DNA in a cell constitutes the cell’s ___, with the DNA molecules packaged into ____

Answer 4

Genome ; chromosomes

Question 5

How many genes does the DNA molecule of a chromosome carry?

Answer 5

Several hundred to a few thousand

Question 6

How does one parent give rise to two genetically identical daughter cells?

Answer 6

• Interphase
• Mitosis
• Cytokinesis

Question 7

What is interphase?

Answer 7

When the cell grows in preparation for cell division; chromosomes are duplicated and copied precisely

Question 8

What is mitosis?

Answer 8

The chromosome copies are separated from each other and moved to the opposite ends of the cell

Question 9

What is cytokinesis

Answer 9

The cell divides into two daughter cells, genetically identical to each other and to the parent cell

Question 10

Eukaryotic chromosomes consist of ___

Answer 10

Chromatin

Question 11

What is chromatin?

Answer 11

A complex of DNA and protein that condenses during cell division

Question 12

What are somatic cells?

Answer 12

Non-reproductive cells; two sets of chromosomes

Question 13

What are gametes?

Answer 13

Reproductive cells (sperm and eggs); half as many chromosomes as somatic cells

Question 14

How are each two sister chromatids attached along their lengths?

Answer 14

By cohesions

Question 15

What is the centromere?

Answer 15

The narrow “waist” of the duplicated chromosome, where the two chromatids are most closely attached

Question 16

During cell division, the two sister chromatids of each duplicated chromosome ___ and move into __ ___

Answer 16

separate ; two nuclei

Question 17

What are the separate chromatids called?

Answer 17

Chromosomes

Question 18

Eukaryotic cell division consists of ___ and ____

Answer 18

• Mitosis
• Cytokinesis

Question 19

What is mitosis?

Answer 19

The division of the genetic material in the nucleus

Question 20

What is cytokinesis?

Answer 20

The division of the cytoplasm

Question 21

What are the phases of the Cell Cycle?

Answer 21

• Gap 1 (G1)
• Synthesis (S)
• Gap 2 (G2)
• Mitosis (M)

Question 22

What occurs during the G1 phase of the cell cycle?

Answer 22

The cell grows and prepares for DNA replication

Question 23

What occurs during the S phase of the cell cycle?

Answer 23

Replication occurs, genetic material is duplicated resulting in two identical sister chromatids

Question 24

What occurs during the G2 phase of the cell cycle?

Answer 24

The cell continues to grow and prepares for cell division

Question 25

What happens during the M phase of the cell cycle?

Answer 25

The nucleus of the cell divides into two daughter nuclei

Question 26

What happens during cytokinesis in the cell cycle?

Answer 26

Division of cytoplasm, producing two daughter cells

Question 27

What are the events of the cell cycle directed by?

Answer 27

The cell cycle control system

Question 28

What are the specific checkpoints where the cell cycle stops until a go-ahead signal is recieved?

Answer 28

G1 ; G2 ; M

Question 29

What are the two types of regulatory proteins involved in cell cycle control?

Answer 29

Cyclins and cyclin-dependent kinases (Cdks)

Question 30

The activity of Cdk ___ and ___ with changes in concentration of its ___ partner

Answer 30

rises and falls ; cyclin

Question 31

Where do Cdks need to be attached to be active?

Answer 31

To a cyclin

Question 32

What is MPF (maturation-promoting factor)?

Answer 32

A cyclin-Cdk complex that triggers a cell's passage past the G2 checkpoint into the M phease

Question 33

What does MPF act as?

Answer 33

Both a kinase and indirectly through activating other kinases

Question 34

What happens if the cell does not receive the go-ahead signal?

Answer 34

It will exist the cycle and switch into the non-dividing state called the G0 phase

Question 35

What happens if a cell does receive the go-ahead signal at the G1 checkpoint?

Answer 35

It will usually complete the S, G2, and M phases and divide

Question 36

What happens to cancer cells during the cell cycle?

Answer 36

The cancer cells do not heed the normal signals that regulate it, and often do not stop dividing when growth factors are depleted