Regulating the Cell Cycle

Question 1

True or False: The controls on cell growth and division can be turned on and off

Answer 1

True

Question 2

True or False: The rate of cell division slows when the healing process nears completion

Answer 2

True

Question 3

What are cyclins?

Answer 3

A family of proteins that regulate the timing of the cell cycle in eukaryotic cells

Question 4

What are internal regulators?

Answer 4

Internal regulators are proteins that respond to events inside a cell

Question 5

What do internal regulators do?

Answer 5

They allow the cell to proceed only once certain processes have happened inside the cell

Question 6

What are external regulators?

Answer 6

External regulators are proteins that respond to events outside the cell

Question 7

What do external regulators do?

Answer 7

External regulators direct cells to speed up or slow down the cell cycle

Question 8

What are growth factors?

Answer 8

Growth factors are external regulators that stimulate the growth and division of cells.

Question 9

When are growth factors useful?

Answer 9

Growth factors are useful during embryonic development and wound healing

Question 10

What is apoptosis?

Answer 10

Apoptosis is a process of programmed cell death

Question 11

When is apoptosis important?

Answer 11

Apoptosis is important in the development of organisms by shaping the structure of tissues and organs

Question 12

What is cancer?

Answer 12

Cancer is a disorder in which body cells lose the ability to control cell growth

Question 13

How is a tumor formed?

Answer 13

A tumor is formed when cancer cells divide uncontrollably to form a mass of cells

Question 14

What is a benign tumor?

Answer 14

A benign tumor is noncancerous

Question 15

What does a benign tumor do?

Answer 15

It does NOT spread to surrounding healthy tissue

Question 16

What is a malignant tumor?

Answer 16

A cancerous tumor

Question 17

What does a malignant tumor do?

Answer 17

It invades and destroys surrounding healthy tissue and can spread to other parts of the body

Question 18

What is the spread of cancer cells called?

Answer 18

Metastasis

Question 19

What do cancer cells do?

Answer 19

Cancer cells absorb nutrients needed by other cells, block nerve connections, and prevent organs from functioning

Question 20

How are cancers caused?

Answer 20

Defects in genes that regulate cell growth and division

Question 21

What are some of the sources of gene defects?

Answer 21

Smoking tobacco, radiation exposure, defective genes, and viral infection

Question 22

What is the most common damaged or defective gene in cancer cells?

Answer 22

The p53 gene

Question 23

What happens when there is a damage or defection in the p53 gene?

Answer 23

It causes cells to lose the information needed to respond to growth signals

Question 24

True or False: Some localized tumors can be removed by surgery

Answer 24

True

Question 25

True or False: many tumors cannot be treated with targeted radiation

Answer 25

False: many CAN be treated with targeted radiation

Question 26

What is chemotherapy?

Answer 26

The use of compounds that kill or slow the growth of cancer cells