Mitosis

Question 1

how do Eukaryotic cells replicate

Answer 1

Mitosis

Question 2

How do Prokaryote cells replicate

Answer 2

Binary fission

Question 3

What are the main stages of the cell cycle

Answer 3

-G1
-G1-S chekpoint
-S
-G2
-G2-M checkpoint
-M

Question 4

what occurs during G phase

Answer 4

-Growth factors trigger the cell to replicate
-Many proteins will be developed in this phase to assist in replication.

Question 5

What happens at the G1-S checkpoint?

Answer 5

This checkpoint allows the cell to determine if its environment allows for replication

If the cell has enough resources

Question 6

What happens at S phase?

Answer 6

DNA synthesis and replication

Question 7

what happens at G2-M checkpoint?

Answer 7

It is an NB checkpoint that determines if the DNA has replicated properly and is not damaged.

If the DNA is damaged,the cell cycle will be paused until it is repaired and if it is too damaged then the cell will undergo apoptosis.

Question 8

What are the stages of mitosis?

Answer 8

-Prophase
-Prometaphase
-Metaphase
-Anaphase
-Telophase
-Cytokinesis

Question 9

what is happens at Prophase?

Answer 9

-Replicated chromosomes, each consisting of two sister chromatids condense
-Mitotic spindle fibre starts to be produced by centrosomes outside the nuceus.

Question 10

What happens during Prometaphase?

Answer 10

-The nuclear envelope breaksdown
-Spindle microtubules attach to chromosomes via their kinetochores and undergo active movement.

Question 11

What is metaphase?

Answer 11

-The chromosomes are alligned at the equator of the cell
-The kinetochores attach sister chromatids to opposite poles of the spindle

Question 12

What is Anaphase?

Answer 12

-The sister chromatids begin to start moving to opposite poles of the cell
-The kinetochore microtubules get shorter

Question 13

What happens during Telohase?

Answer 13

-The two sets of daughter chromosomes arrive at opposite poles of the cell and decondense
-The nuclear envelope begins to reassemble around each set
-A contractile ring begins to form in the middle of the cell.

Question 14

What happens during Cytokinesis?

Answer 14

-The cytoplasm divides in two by the pinching of the contractile ring of actin and myosin in between the cell to create two new daughter cells.

the chromatin network unwinds before this phase ends so that transcription can start to occur

Question 15

What are CDK’s?

Answer 15

-Cdks are proteins kinases that phosphorylate other intracellular proteins to promote the cell cycle
-Cdks activated by binding to cyclins
-There are unique cyclin/cdk pairs that activate progression through the various phases of the cell cycle.

Question 16

What are the G1/s-cyclins

Answer 16

-They activate cdks in late G1 and trigger progression through the restriction point
_Growth factor stimulates the build up of these CDKS.

Question 17

What are the S-cyclins

Answer 17

They bind cdks after restriction point.Stimulate chromosome duplication
-they start to build up after the s-checkpoint and when they reac peak, S phase starts.
-The s-cyclin must remain high until mitosis occurs in order for cell to tolerate extra DNA

Question 18

What are the M-cyclins

Answer 18

They activate cdks that allow progression through the G2/M checkpoint.
-They tell the cell that the DNA is in good condition and it can begin to start replicating

when mitosis starts, all CDK levels drop