Cell Cycle

Question 1

What is the purpose of cell division?

Answer 1

Cell replacement, tissue renewal, growth, development, and asexual reproduction.

Question 2

Give three examples of asexual reproduction.

Answer 2

Amoeba reproduction, regeneration of a sea star, growth from a plant clipping.

Question 3

Define genome.

Answer 3

All the genetic material in a cell.

Question 4

Define chromosome.

Answer 4

A single DNA molecule associated with proteins that contains genetic information.

Question 5

Define chromatin.

Answer 5

The complex of DNA and proteins that makes up chromosomes.

Question 6

What are somatic cells?

Answer 6

Body cells that are diploid (2n) normal cell

Question 7

Define sister chromatids.

Answer 7

Identical copies of a chromosome joined at a centromere.

Question 8

Define centromere.

Answer 8

The region where sister chromatids are attached.

Question 9

List the main stages of the cell cycle.

Answer 9

Interphase (G1, S, G2) and Mitotic phase (Mitosis and Cytokinesis).

Question 10

What happens during G1 phase?

Answer 10

Duplicating organelles. 8-10hr

Question 11

What happens during S phase?

Answer 11

DNA replication occurs. 8 hourd

Question 12

What happens during G2 phase?

Answer 12

Cell prepares for division

Question 13

What occurs during the Mitotic phase?

Answer 13

Cell division

Question 14

List the stages of mitosis.

Answer 14

Prophase, Metaphase, Anaphase, Telophase.

Question 15

What happens during prophase?

Answer 15

Chromosome condenses and the mitotic spindle begins to form and nuclear envelope breaks down

Question 16

What happens during late prophase?

Answer 16

Nuclear envelope breaks down and spindle fibers attach to kinetochores.

Question 17

What happens during metaphase?

Answer 17

Chromosomes align at the metaphase plate.

Question 18

What occurs during anaphase?

Answer 18

Sister chromatids separate and move toward opposite poles.

Question 19

What occurs during telophase?

Answer 19

Nuclear membranes reform and chromosomes begin to decondense.

Question 20

Define mitotic spindle.

Answer 20

A structure made of microtubules that separates chromosomes during mitosis.

Question 21

Define kinetochore.

Answer 21

A protein structure on chromatids where spindle fibers attach.

Question 22

What is cytokinesis?

Answer 22

Division of the cytoplasm to form two daughter cells.

Question 23

How does cytokinesis differ between animal and plant cells?

Answer 23

Animal cells form a cleavage furrow; plant cells form a cell plate.

Question 24

What is binary fission?

Answer 24

A type of asexual reproduction used by bacteria to divide.

Question 25

What molecules control the cell cycle?

Answer 25

Cyclins and cyclin-dependent kinases (Cdks) which form MPF (maturation/mitosis promoting factor).

Question 26

Name the three major checkpoints in the cell cycle.

Answer 26

G1 checkpoint, G2 checkpoint, and M (Anaphase) checkpoint.

Question 27

What happens at the G1 checkpoint?

Answer 27

Determines whether the cell will divide or enter G0 phase.

Question 28

What happens at the G2 checkpoint?

Answer 28

Checks for DNA damage and proper replication before mitosis.

Question 29

What happens at the M checkpoint?

Answer 29

Ensures all chromosomes are properly attached to spindle fibers before separation.

Question 30

What is PDGF?

Answer 30

Platelet-derived growth factor that stimulates cell division.

Question 31

Define density-dependent inhibition.

Answer 31

Cells stop dividing when they become crowded.

Question 32

Define anchorage dependence.

Answer 32

Cells must be attached to a surface to divide.