Unit 5: Cancer cells

Question 1

What are the 3 checkpoints and what are they checking for?

Answer 1

G1 checkpoint: restriction point, makes sure it wants to duplicate, if it does it keeps going, if it doesn’t it goes to G0
checking for: nutrients, cell density (space), growth factors, anchored (holding on)

G2 to M checkpoint: make sure DNA looks good. Checking: synthesis (replication) is done, DNA is not damaged or mutated

M (metaphase) checkpoint: making sure cell is ready to divide. Checking: are all the kinetochores properly attached to microtubules

Question 2

what is G0 and why does it happen

Answer 2

when the cell rejects the 1st checkpoint, G0 is resting state, wait until it’s needed

Question 3

what is a CDK and a cyclin? how do they work together

Answer 3

CDK –> cyclin dependent kinase
Cyclin –> activator of CDK
protein level of cyclins “cycle” during the cell cycle
phosphorylates with ATP to add a phosphate to a protein

Question 4

3 types of cancer genes and their analogy

Answer 4

1. gas pedal sticks, oncogenes= go go go!
2. Brake pedal Breaks, tumor suppressor = no stop
3. the mechanic, fixes DNA mutations = bad parts

Question 5

pathway to cancer –> 4 types of cells

Answer 5

normal cell –> benign tumor –>malignant tumor –> metastatic tumor

Question 6

how do checkpoints work? 2 things

Answer 6

1. activators (gas pedal), nutrients, growth factors
   CDK+Cyclin=Go!
2. Inhibitors (brake pedal) no space, not anchored
   tumor suppressor =stop!

Question 7

what factors of checkpoint G1 tell to go

Answer 7

nutrients and growth factors

Question 8

what factors of checkpoint G1 say don’t go

Answer 8

space and anchor

Question 9

how does the levels of protein affect CDK and Cyclin differ

Answer 9

CDK is a straight line

Cyclin has a high protein spikes at S thru M then it goes back down

Question 10

what causes a benign tumor

Answer 10

gas pedal: no, cells replicates
Space brake pedal: yes, stop when space runs out
Anchor Brake pedal: yes, stay in one place

Question 11

what causes a malignant tumor

Answer 11

gas pedal: no, cell replicates
space brake pedal: no takes over the space
anchor brake pedal: yes stays in one place

Question 12

What causes a metastatic tumor

Answer 12

gas pedal: no, cell replicates
space brake pedal: no takes over the space
anchor brake pedal: no, move around the body