Test #3- Cell division Regulation

Question 1

What does cell division the fastest?

Answer 1

Embryo cells

Question 2

What cell never does cell division after it is matured?

Answer 2

nerve and muscle cells–> permantley in G0

Question 3

What happens at the G1/S checkpoint?

Answer 3

It makes sure that the DNA is all correct (and checks for errors) before it duplicates the DNA

Question 4

What happens at the G2/M checkpoint?

Answer 4

It evaluates the accuracy of the DNA replication and signals whether or not to start mitosis–> repairs any damage

Question 5

What happens at the M checkpoint?

Answer 5

during metaphase–> ensures that the mictotubules are properly attatched to all kinetochores before division continues.

Question 6

How does the cell send the signal to the checkpoints?

Answer 6

Chemical signals in cytoplasm

Question 7

What are 3 cell cycle signals?

Answer 7

cyclins-active
kinases-inactive
cdk-cyclin complex

Question 8

What 2 things should inhibit growth in a normal cell?

Answer 8

Density dependent inhibition

Anchorage dependence

Question 9

What are 2 things that prevents cancer in our body?

Answer 9

Proto-oncogenes (want them OFF)

Tumor-suppressor genes (eg. p53–> want them ON)

Question 10

What are 2 kinds of tumors? Which is more dangerous?

Answer 10

benign tumor- abnormal cells remain at original site as a lump
malignant tumor-cells leave original site–carried by blood and lymph to other tissues (More dangerous)