BIOL340 - QUIZ 3 EXAM QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
what are the 2 phases in the cell cycle, and which one takes the longest
1. Interphase: G1, S, G2
2. M phase
- interphase is the longest
What happens in G1 phase
cell growth and organelles duplicate
What happens in S phase
DNA and chromosomes replicate
What happens in G2 phase
cell grows, preparing for mitosis and centrosome duplicates and chromosomes condense
what happens in M phase
= mitosis
- its the segregation of the replicate chromosomes
What are the major checkpoints in cell cycle
,1. G1 -> S
2. G2 -> M
3. M-> anaphase
What happens in G1->S
major decision made - will cell divide again, cells that wait for signal to divide are in G0 phase.
what stimulates cell to divide or not
external factors such as growth factors or cytokines
- leads to cascade of signals
What is M phase made up of
Mitosis (replicated chromosomes separated into 2 nuclei) and Cytokinesis (cytoplasm of cell divides into
2 daughter cell)
What controls the cell cycle progression (checkpoints). What does G1-> and G2->M transitions mainly
rely on
the assembly, activation and disassembly of Cdk's (protein kinases) govern the activity and allow
progression through cell cycle. They're activated by specific cyclins
what are cdk-cyclin complexes
cdks = cyclin dependent kinase (subunit with ser/thr kinase activity)
cyclins = regulatory subunit
what are the 2 cyclins
G1 cyclins and mitotic cyclins
, how do concentration levels of cyclin effect cell cycle
the levels are controlled at 2 points (G1->S and G2-M)
- G1 cyclins rise at G1 and fall by G2->M
- Mitotic cyclins low at G1 and rise at M phase
what are the bindings between cyclins and cdk's
cyclin D binds to cdk4,6 (G1 phase)
cyclin E binds to cdk2 (G1-S phase)
cyclin A binds to cdk2 (S phase)
cyclin A/B binds cdk 1 (G2-M phase)
what are the 6 steps of controlling cdk activity
1. cyclin binding
2. synthesis of cyclins and cdks
3. controlled proteolysis
4. phosphorylation of cdk
5. subcellular localisation
6. checkpoints/cdk inhibitors
1. what happens when cyclin binds to cdk
causes conformational change in the cyclins catalytic subunit - allows active site to be exposed
- it allows activated cdk to phosphorylate proteins for transition
2. how does G1 cdk-cyclin effect Rb protein
WITH COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
what are the 2 phases in the cell cycle, and which one takes the longest
1. Interphase: G1, S, G2
2. M phase
- interphase is the longest
What happens in G1 phase
cell growth and organelles duplicate
What happens in S phase
DNA and chromosomes replicate
What happens in G2 phase
cell grows, preparing for mitosis and centrosome duplicates and chromosomes condense
what happens in M phase
= mitosis
- its the segregation of the replicate chromosomes
What are the major checkpoints in cell cycle
,1. G1 -> S
2. G2 -> M
3. M-> anaphase
What happens in G1->S
major decision made - will cell divide again, cells that wait for signal to divide are in G0 phase.
what stimulates cell to divide or not
external factors such as growth factors or cytokines
- leads to cascade of signals
What is M phase made up of
Mitosis (replicated chromosomes separated into 2 nuclei) and Cytokinesis (cytoplasm of cell divides into
2 daughter cell)
What controls the cell cycle progression (checkpoints). What does G1-> and G2->M transitions mainly
rely on
the assembly, activation and disassembly of Cdk's (protein kinases) govern the activity and allow
progression through cell cycle. They're activated by specific cyclins
what are cdk-cyclin complexes
cdks = cyclin dependent kinase (subunit with ser/thr kinase activity)
cyclins = regulatory subunit
what are the 2 cyclins
G1 cyclins and mitotic cyclins
, how do concentration levels of cyclin effect cell cycle
the levels are controlled at 2 points (G1->S and G2-M)
- G1 cyclins rise at G1 and fall by G2->M
- Mitotic cyclins low at G1 and rise at M phase
what are the bindings between cyclins and cdk's
cyclin D binds to cdk4,6 (G1 phase)
cyclin E binds to cdk2 (G1-S phase)
cyclin A binds to cdk2 (S phase)
cyclin A/B binds cdk 1 (G2-M phase)
what are the 6 steps of controlling cdk activity
1. cyclin binding
2. synthesis of cyclins and cdks
3. controlled proteolysis
4. phosphorylation of cdk
5. subcellular localisation
6. checkpoints/cdk inhibitors
1. what happens when cyclin binds to cdk
causes conformational change in the cyclins catalytic subunit - allows active site to be exposed
- it allows activated cdk to phosphorylate proteins for transition
2. how does G1 cdk-cyclin effect Rb protein
