Chapter 10.2 Unit 3

Question 1

What happens when chromosomes super condense?

Answer 1

It can’t read DNA

Question 2

What are cohesion proteins?

Answer 2

They are chromatids held closely together.

Question 3

What is attached to the kinetochore?

Answer 3

Microtubules

Question 4

What happens in G2 when the chromosomes condense?

Answer 4

They become tightly coiled.

Question 5

During Interphase what do Centrioles do?

Answer 5

They replicate and move to each end or pole of the cell.

Question 6

List the five phases of mitosis

Answer 6

1. Prophase
2. Prometaphase
3. Metaphase
4. Anaphase
5. Telophase

Question 7

What are some characteristics of Prophase?

Answer 7

The chromosomes further condense, centrioles move to each pole (anchors pull sister chromosomes apart), spindle apparatus is assembled and the nuclear envelope dissolves

Question 8

What is the nuclear envelope?

Answer 8

It is a double membrane which surrounds the nucleus within the cell.

Question 9

What are some characteristics of Prometaphase?

Answer 9

Sister chromosomes become attach to the spindle apparatus by their kinetochores, A second set of microtubules is formed from the poles to each kinetochore, and the microtubules begin to pull each chromosome toward the center of the cell

Question 10

What are centrioles?

Answer 10

They are a set of small microtubules which are arranged in a specific way.

Question 11

What are some characteristics of Metaphase?

Answer 11

The microtubules pull the chromosomes to align them at the center of the cell, and sister chromatids line up on the metaphase plate.

Question 12

What is the metaphase plate?

Answer 12

It is an imaginary plane through the center of the cell.

Question 13

What are some characteristics of Anaphase?

Answer 13

It is where the removal of cohesion allows the centromeres to separate, the microtubules pull sister chromatids toward the poles and in anaphase A the kinetochores are pulled toward the poles.

Question 14

What are some characteristic of Telophase?

Answer 14

It is where spindle apparatus disassembles, the nuclear envelope forms around each set of sister chromatids, chromosomes begin to uncoil and nucleus reappears in each new nucleus.

Question 15

What is cytokinesis?

Answer 15

It is the cleavage of the cell into halves so the division of a cell.

Question 16

What is Telophase the opposite of?

Answer 16

It is the opposite of prophase

Question 17

What is cleavage furrow?

Answer 17

It is a structure formed in cytokinesis of an animal cell.

Question 18

What forms a cell plate?

Answer 18

Plasma membrane in plants.

Question 19

What is a cell plate formed by?

Answer 19

Vesicles

Question 20

Does the nuclear membrane break down?

Answer 20

No it does not

Question 21

For what does mitosis occur in the nucleus?

Answer 21

For fungi and some protist

Question 22

What are the three checkpoints?

Answer 22

It is from G1 to S, from G2 to mitosis, and from metaphase to anaphase.

Question 23

What are cyclins?

Answer 23

Proteins produced in synchrony with the cell cycle

Question 24

What is Cyclin-dependent kinases (Cdks)?

Answer 24

Enzymes that drive the cell cycle.

Question 25

When are Cyclin-dependent kinases (Cdks) activated?

Answer 25

When bound by a cyclin

Question 26

What do Cdks activate?

Answer 26

They activate proteins by phosphorylation

Question 27

What is the checkpoint from metaphase called?

Answer 27

The spindle checkpoint

Question 28

What happens in the first checkpoint from G1 to S?

Answer 28

The cell decides to divide

Question 29

What happens in the second checkpoint from G2 to M?

Answer 29

The cell makes a commitment to mitosis

Question 30

What happens in the final checkpoint from metaphase to anaphase?

Answer 30

The cell ensures the chromosomes are attached to the spindle before dividing

Question 31

What is APC?

Answer 31

It stands for Anaphase-promoting complex

Question 32

What does APC do?

Answer 32

It is what the signal that proceeds from metaphase to anaphase is transmitted through

Question 33

What does APC activate?

Answer 33

It activates proteins which remove the cohesion holding sister chromatids together

Question 34

What is chromatin made of ?

Answer 34

It is made of a complex of DNA and proteins (Histones).

Question 35

What does a growth factor do?

Answer 35

It triggers intracellular signals that override cell controls that other whist inhibit cell division.

Question 36

What is an example of growth factor?

Answer 36

It is Platelet-derived growth factor (PDGF)

Question 37

What does PDGF do?

Answer 37

It triggers cells to divide during wound healing.

Question 38

What is cancer?

Answer 38

It is the failure of cell cycle control, resulting in runaway cell division.

Question 39

What are the two kinds of genes that can cause cancer when mutated?

Answer 39

Tumor-suppressor genes and proto-oncogenes

Question 40

What are tumor suppressor genes?

Answer 40

They are normally the breaks which prevent division in cells containing mutations.

Question 41

What are proto-oncogenes?

Answer 41

They are normally the gas which code for growth factors or signal transduction proteins that promote normal cell division.

Question 42

What are two examples of tumor suppressor genes?

Answer 42

p53 and Rb

Question 43

What can cause cancer when introduced into a new cell?

Answer 43

Oncogenes