Explain the Cell Cycle doctrine and early cell experiments.
Which came first the chicken of the egg. Well all cells in the chicken can be traced back to the egg. And all cells in the egg can be traced back to the
Critics of plays notice the amount of time
All new cells originate from other living cells
Every cell in your body can be traced back to your zygote via mitosis. In a broader sense the zygote can be traced further to the parents via meiosis. In a boraders sense these two types of cell division lin
How long is the cell cycle for yeast vs mammals
2hours and 1- several days for mamals
What happens in G1
G1 = 1 god G-d
growth and duplication of organelles
s
DNA replication and chromosome duplication
G2
( The muscle man bulks up and prepares for his competition
Cell grows and prepares for mitosis
What controls the cell cycle
Diffusable proteins
Explain the overarching concept of Cell cycle control
When Satan and G1-D fought for control of heaven originally Satan was able to take control. Michael helped helped g1-D by convincing him to follow his plan
When a g1 phase cell is combined with an s phase cell, that cell will recieve diffusable proteins from sphase cell and begin DNA replication/ organelle duplication.
If the g1 phase cell combines with an m phase cell then that cell will begin mitosis
Hi all future dentists. The DAT is the main factor of whether one matures into a dentist. The Dat differs from the mcat in that it has regular science questions that are cycled from year to year. Also the Mcat has a physical kinetics subsection while the
The maturation promoting factor is a diffusable protein that controls whether a cell enters the m phase of the cell cycle. The MPF has a regulatory subunit (cyclin) and a kinase (cdk). The activity of the maturation promotion factor corresponded to the pr
CDK's
Certificate of Deposists help your progress through the changing stages of the market event if you don't make much money that depends on interest rates which cycle. Hence the money can sit there unless activated by a bull cyclical stage in the marke
Cylcin dependent kinases help the cell progress through the cell cycle. Remember, that Cyclin dependent kinases are always present in the cell. They are only active when bound to cyclin.
Cyclins are also involved in protein selection for kinases
The cycling ability of lance armstrong changes with different phases of the race. For example he cycles hard on grade 1 hills until he reaches the restricition point. But the he cycles again from the andes mountains the the bottom of the grade 2 hills
No they don't! Cyclin levels change with the different phases of the cell cycle. For example, G1 Cyclin is transcribed during early G1 but stops at the restriction point (start) i. e halfway through g1. The M cyclin is transcribed in early anaphase and de
The progression through the cell cycle is controlled by cyclin dependent kinases. But at what points do they exhibit their control.
A barmitzvah, marriage, and having kids are the three commited steps to becoming a mench
G1- S- Restriction point (start point yeast)
G2-M boundary junction of metaphase and anaphase
G1- S phase
At a barmitzvah the child grows by becoming a man.
At this point the cell checks to make sure DNA fully committed to enter the S phase and relies on external growth factors
G2-M
the second commited regulatory step that dictates whether a cell enters mitosis
Junction of Metaphase and Anaphase
The third commited regulatory step that makes sure the spindle is firmly attached to the chromomosomes and ensures proper segreagation of chromatids
How are CDK/Cylin controlled in general.
The aepi's CRAK on his CAP gave his pitch some CIK that put the Cig Ki's A team in a bind and led their complete annihilation and degradation.
First CDKs are only active when bound to cyclins.
Cyclins production is regulated at the genetic level.
CDK activation is controlled by phosphorylation via kinases
- CAK- CDK activating kinase, which phosphorylates cdk when bound to cyclin
-CIK- CDK inhib
CAK
phosphorylates cdk when bound to cylcin
The cik and cap are regulated by and examples respectively
Weed is better for you then crack
extracellular conditions,
Cik Wee1- kinase and overides cak
Cap-cdc25
CigKI (CKI)
27 people
CDK inhibitor protein binds to the active site of the CDK
How is mitotic CDK controlled/ produed (The weed green crack sells for 25 dollars)
Well in the G1S Cyclin binds to CDK and two inhibitory phosphates are added. Then in the late G2 phase, Cak, adds a phosphate which remains inactive until the CDC25 removes the inactive phosphates
Mitotic CDC can form a positive feeback loop with
CDC 25
In what stages does M cyclin accumulate but remain inactive
g1+S
When is M cylin fully active
at the end of g2
`What happens when mitotic cdk is produced
It helps lead to set the stage for mitotic events
activating maps via phosphorylation (maps, proteins involved in production of mitotic spindle)
chromosomes condensation- via condensin
nuclear envelope breakdown- lamina depolymerized when phosphorylated b
Activted mitotic CDK stimulin stimulates
1. Nucleaur Envelope break down
2 Chromosome Condensation
3. Spindle Formation
4. Targeted protein degradation
ubiquitin ligase
- Enzyme that is largely responsible for recognition of the particular proteins to be ubiquinated and thus tagged with ubiquitin for destruction
adds ubiquitin to the cyclin molecule
Anaphase promoting complex
obviously promotes anaphase so in the process need to destroy mitotic cyclin dependent kinase:
- In order to do this it must be phosphorylated via mitotic cdk, and then interacts with CDC 20 (phosphorylase) which activates it.
- The active apc ubiquilates
Explain how ubiquitin ligases work
E1 is the Ub activating enzyme that uses ATP to add UB to the E1
E2 is the UB conjugating enzyme
E3 is the UB ligase
It has substrate specificity at the lysine residues and binds E2
Ubiquiton is a short peptide
The marked protein is degraded by the proteo
Summarize the control of M cylin
Well in the g1 phase and s phase the cylin binds cdk and is phosphorylated with inactive phosphates. By late G2 phase the activating kinase + phosphotase removes the inactive phosphates allow the M cyclin to be activated. The activated M cyclin can phosph
The M cyclin is degraded by the APC in the
late M phase
How does G1 Cylin allow progression through cell cycle
Remember G1 synthesis is activtated by anything that makes you grow. Particullary growth factor which activates the RAS pathway. The Ras pathway leads to production of the CDK G1 Cyclin that phosphorlyates Retinal blastoma causing it to dissociate from th
If the cell does not meet a requirment of a checkpoint it will undergoe. And what are the three checkpoints and what do they check
apoptosis,g1 DNA damage
g2, DNA replication,
M- Mitotic Spindle
Explain how the G1 Checkpoint works
After the talent agent had his eyes checked at clarkson eye care he went to the atm and pulled out 53 dollars. He decided he would only spend 21 dollars of that money, hence he restricted himself. So he went to the puma
MGM2 is a a ubiqulated ligase that stops p53 from being phosphorylated in normal cells. But it cells with damaged DNA, p53 is phosphorylated via ATM kinase . The p53 activates the p21 which inhibits g1 cyclase stopping the retinoblastoma from getting phos
What two proteins ensure that cells with damage DNA do not undergoe cell division
Puma and p21
DNA replication checkpoint (G2)
ATR check -CDC 25
ensures that DNA has been replicated before cell exists G2 and enters mitosis. This mechanism involves stalled DNA replication forks. Which activates an ATR. Which activates CHk1 and Chk2 that phosphorylate and inhibit CDC 25. So cant remove So M cyclin d
Metaphase anaphase transition check - CDC 20 sequesteration
all chromosomes attached to spindle apparatus. Mad and Bub are proteins that attach to centromemere. They sequester cdc 20. via Mad and Bub. When spindle appartus forms it will displace Mad and Bub enabling it to interact with Anaphase complex. So if all
RAS PATHWAY
...