Exam 3 - Cancer

Question 1

What is a neoplasm?

Answer 1

an abnormal growth of cells

Question 2

What does it mean if a neoplasm is benign?

Answer 2

• not cancerous
• encapsulated by connective tissue
• non- invasive

Question 3

What does it mean if a neoplasm is malignant?

Answer 3

• not encapsulated
• invasive of neighboring tissue
• metastasis
• results from a mutation of genes regulating the cell cycle

Question 4

What does metastasis mean?

Answer 4

detach and lodge in distant places
- tumors easily fragment
- transported around body

Question 5

carcinogenesis?

Answer 5

development of cancer

Question 6

carcinogens?

Answer 6

things that could cause cancer

Question 7

mutagens?

Answer 7

can cause mutations in genes

Question 8

What are the characteristics of cancer cells?

Answer 8

• lack differentiation
• have abnormal nuclei
• form tumors
• undergo metastasis
• undergo angigenisis

Question 9

what does it mean that cancer cells lack differentiation?

Answer 9

non-specialized ( don’t contribute to any function)

Question 10

How do cancer cells form tumors?

Answer 10

• mitosis controlled by contact with neighboring cells
• contact inhibition = cells touch= they stop dividing
• cancer cells have lost contact inhibition

Question 11

what does it mean that cancer cells undergo angiogenesis?

Answer 11

• formation of new blood vessels –> they funnel nutrients and hog it from normal cells

Question 12

What is a carcinoma?

Answer 12

A cancer in the epithelial tissue

Question 13

What is a sarcoma?

Answer 13

Connective tissue. bone and muscle

Question 14

what is leukemia? lymphoma?

Answer 14

• blood-forming organs
• immune system

Question 15

What are the origins of cancer?

Answer 15

mutations in DNA repair mechanisms

Question 16

What are proto-oncogenes? What can they mutate into?

Answer 16

promote ( stimulatory) cell cycle in various ways
- mutate into oncogenes

Question 17

What do tumor suppressor genes do?

Answer 17

-Inhibit the cell cycle

Question 18

what is an oncogene?

Answer 18

cancer-causing genes permanently turn on the cell cycle

Question 19

Mutations in which genes cause the growth of tumors?

Answer 19

• proto-oncogenes
• tumor suppressor genes
• both normally regulated in coordination with an organism growth plan
• if either mutates may lose control of the cell cycle = tumor formation

Question 20

what is the most common mutation that leads to cancer?

Answer 20

P53 from G1 checkpoint

Question 21

What is telomerase?

Answer 21

an enzyme that adds telomeres to the end of chromosomes

Question 22

what are telomeres?

Answer 22

repeat sequences and specialized proteins at the tips of chromosomes

Question 23

what is supposed to occur to telomeres as time goes on?

Answer 23

• get shorter with each cell division
• once very short they no longer divide

Question 24

what happens when telomerase is mutated?

Answer 24

• keep adding telomeres
• cancer cells continually divide = immortal cancer cells
• 85-95% of cancers