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

Carbohydrates, what is the structural formula for Galactose?

what is the structural formula for Galactose?

Continuous suture technique-prosthetic aortic valve, Continuous suture tec...

Continuous suture technique: Monofilament 2'0' prolene sutures, which slide through easily, are used for this technique. three double armed prolene sutures are taken and with val

Factors that limit the reproductive potential, Organisms are made to compet...

Organisms are made to compete for their needs from the environment. The competition as we pointed earlier could be for the food and territory, to overcome the adverse climatic cond

What are the reticular fibers of the connective tissue, Q. What are the ret...

Q. What are the reticular fibers of the connective tissue and where they can be found? The reticular fibers are especially delicate interstitial fibers made of a special kind o

How far from the building should the fire hose be located, A fire hose ejec...

A fire hose ejects a stream of water at an angle of 38.8 ° above the horizontal. The water leaves the nozzle with a speed of 26.6 m/s. Assuming that the water behaves like a projec

De vega annuloplasty, De Vega Annuloplasty :  Classic De Vega annulop...

De Vega Annuloplasty :  Classic De Vega annuloplasty is done using 2'0' double armed polyester suture with pledgets on either end. It starts with one of the needles passed fr

Plants - slow moving waters, Plants - Slow Moving Waters Plant life is...

Plants - Slow Moving Waters Plant life is abundant in this habitat and includes rooted vascular plants such as pond weeds and grasses, firmly attached aquatic mosses and multi

Gonad glands, what are the gonad gland disorders and what do they do

what are the gonad gland disorders and what do they do

Cellular type - endosperm, Cellular Type - Endosperm In this type, as...

Cellular Type - Endosperm In this type, as the name indicates, the division of the primary endosperm nucleus is immediately followed by the laying down of a wall, which is us

Define the respiratory chain process, Q. Where in mitochondria does the pro...

Q. Where in mitochondria does the process called respiratory chain occur? Which are the products of the Krebs cycle used in that final phase of the aerobic respiration? Respira

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