Control of the cell cycle, Biology

Assignment Help:

The cell cycle is controlled by a cyclically operating set of reaction sequences that both trigger and coordinate key events in the cell cycle

• The cell-cycle control system is driven by a built-in clock that can be adjusted by external stimuli (chemical message).

• Checkpoint - a critical control point in the cell cycle where stop and go-ahead signals can regulate the cell cycle
o Animal cells have built-in stop signals that halt the cell cycles and checkpoints until overridden by go-ahead signals.
o Three Major checkpoints are found in the G1, G2, and M phases of the cell cycle.

• The G1 checkpoint - the Restriction Point
o The G1 checkpoint ensures that the cell is large enough to divide, and that enough nutrients are available to support the resulting daughter cells.
o If a cell receives a go-ahead signal at the G1 checkpoint, it will usually continue with the cell cycle
o If the cell does not receive the go-ahead signal, it will exit the cell cycle and switch to a non-dividing state called G0
o Actually, most cells in the human body are in the G0 phase.

• The G2 checkpoint ensures that DNA replication in S phase has been completed successfully.
• The metaphase checkpoint ensures that all of the chromosomes are attached to the mitotic spindle by a kinetochore. 


Related Discussions:- Control of the cell cycle

Calculate the probability that both are carriers for tsd, The male had a fe...

The male had a female first cousin (on his father side) who died from TSD and the female had a maternal uncle with TSD. Assume this trait is very rare. 1. Calculate the probabil

Explain algae have cell wall, Algae have cell wall made up of: 1. Cellul...

Algae have cell wall made up of: 1. Cellulose, galactans and mannans 2. Hemicellulose, pectins and proteins 3. Pectins, cellulose and proteins 4. Cellulose, hemicellulo

Illustrate about the primary minerals, Illustrate about the primary mineral...

Illustrate about the primary minerals The minerals originally formed when once -heated magma (molten rock) cooled and formed solid igneous rocks (explained below) are called as

Explain the term direct calorimetry, Explain the term Direct Calorimetry? ...

Explain the term Direct Calorimetry? Calorimetry refers to the measurement of the amount of heat evolved or absorbed in a chemical reaction, change of state, or formation of a

Blood pressure, An adequate level of pressure is needed in the arteries to ...

An adequate level of pressure is needed in the arteries to keep the blood flowing through the cardiovascular system. The chief determinant of arterial pressure is the volume of blo

Peri operative myocardial infarction, Peri operative Myocardial Infarction ...

Peri operative Myocardial Infarction :  Peri operative Myocardial Infarction is diagnosed by the appearance of fresh Q waves. Non-Q, myocardial infarction is suspected when there

Signify the difference between bryophytes and tracheophytes, Which of the b...

Which of the below determines the major difference between bryophytes (pron: bry-oh-fites) and tracheophytes (pron: tray-key-o-fites)? a) Tracheophytes can make their own food

Values of dpd for plant cells under hypertonic media, Q. What are the value...

Q. What are the values of DPD for plant cells under hypertonic, hypotonic and isotonic media? In plant cells under hypertonic medium there is loss of water for the external, SF

Poo, BBBBBBBBBBBBBiiiiiiiiiiittttttttttcccccccchhhhhhhhhhhhhhh ass cunt.

BBBBBBBBBBBBBiiiiiiiiiiittttttttttcccccccchhhhhhhhhhhhhhh ass cunt.

Bacterial food poisoning, Bacterial food poisoning Food poisoning is a...

Bacterial food poisoning Food poisoning is an acute gastro-enteritis or intestinal disorder resulting from the ingestion of foods contaminated with either living microorganism

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd