Topic 10 Apoptosis and Cancer

Question 1

What are the 5 stages of Embryonic Development?

Answer 1

1) Fertilization
2) Cleavage
3) Gastrulation
4) Neurulation
5) Organogenesis

Question 2

What is Apoptosis?

Answer 2

it is a process where by cells commit suicide/programmed cell death which uses special cellular material to induce death

Question 3

what are the 2 functions of Apoptosis and some examples?

Answer 3

1) Control Cell Numbers
( removal of tissue between toes and fingers in embryonic development )

2) Eliminate cells that threaten survival of organism
( Cell infected with virus )
( immune cells attacking body )
( Cells with damaged DNA )
( Cancer Cells )

Question 4

What are the 5 stages of how apoptosis occur?

Answer 4

1) Cell Shrinks and develops blebs on the surface (bleb means rounded outgrowth)
2) DNA and protein in nucleus starts to degrade
3) Mitochondria breaks down and releases Cytochrome C
4) Cytochrome C activates enzyme called caspases
5) Caspases cause cell to burst

Question 5

How does apoptosis help in embryonic development?

Answer 5

it helps the maturation of gametes and embryonic development by ensuring that various structures and organs develop properly

Question 6

What are the 2 causes that make the cell commit suicide?

Answer 6

1) Lack/withdrawal of positive signals
2) the Receipt/receiving of negative signals

Question 7

how is apoptosis regulated?

Answer 7

Apoptosis is regulated by anti apoptotic genes and pro apoptotic genes. anti apoptotic genes make protein that prevent cell death while pro apoptotic genes make protein that cause cell death

Question 8

What are examples of Anti apoptotic genes?

Answer 8

1) Bcl-2 gene

Question 9

What are examples of Pro apoptotic genes?

Answer 9

1)Bax gene
2) P53 gene

Question 10

How does Bax gene kill a cell?

Answer 10

1) Bax gene code for Bax protein
2) Bax protein binds to mitochondria and makes more holes on mitochondria increasing permeability
3) Increase in permeability triggers cell death
4) Mitochondria releases Cytochrome C and than cell die

Question 11

What is the 2 functions of mitochondria?

Answer 11

1) Produce energy
2) Facilitate cell death through apoptosis

Question 12

How is Apoptosis and Cancer related?

Answer 12

1) Over expression of anti- apoptotic genes causes cell to grow uncontrollably
2) Under expression of pro- apoptotic genes causes cell to grow uncontrollably

Question 13

What is Cancer?

Answer 13

A cell that grows uncontrollably and eventually spread throughout the body and interfere with tissue and organ functions

Question 14

What is the 4 properties of Cancer Cells?

Answer 14

1) they do not differentiate
2) do not die from old age ( Immortal )
3) do not respond to signals
4) do not grow quickly

Question 15

What is metastasis?

Answer 15

metastasis is when a cancer cell spreads and invade surrounding tissues and causes secondary areas of growth

Question 16

What are tumor suppressor genes?

Answer 16

1) Genes that protect cell from cancer
2) Necessary for apoptosis
3) mutation of this gene will cause harmful effects

Question 17

What are the general causes of Cancer?

Answer 17

1) spontaneous genetic mutation
2) Inherited susceptibility to cancer
3) carcinogenic substances
4) Viruses
5) Radiation
6) Hormonal imbalances
7) Stress
8) Diet
9) Smoking
10) Lack of excercise

Question 18

What are the 3 main groups of Cancer?

Answer 18

1) Carcinomas
2) Sarcomas
3) Leukemias, Lymphomas

Question 19

how does p53 gene work?

Answer 19

if a DNA in a cell is damaged the p53 gene is expressed stopping the cell cycle immediately leading to apoptosis

(if p53 gene is damaged the cell cycle continues with will lead to more replication of damaged DNA that may lead to cancer)