Apoptosis


Apoptosis is a biological mechanism which is one type of programmed cell death. Apoptosis is used by multicellular organisms to remove cells that are not needed by the body.

Apoptosis is different from necrosis. Apoptosis is generally lasts a lifetime and be beneficial for the body, while necrosis is cell death caused by cellular damage acutely.

A concrete example of the advantages is the separation finger apoptosis in embryos. Apoptosis experienced by the cells located between each finger causes the finger to be separated from each other. When cells lose the ability to perform the apoptotic cells can divide indefinitely and eventually become a cancer.


Apoptosis has distinctive morphological characteristics such as plasma membrane blebbing, cell shrinkage, chromatin condensation and DNA fragmentation, and begins with the enzymes of the caspase proteases form a complex group of Cysteine protease activation of multi sub-unit called apoptosom.

Apoptosis can occur for example when the cell damage that is irreversible. The decision to perform apoptosis comes from the cell itself, from the surrounding tissue, or from cells derived from the immune system.

An estimated 50-70 billion cell die each day due to apoptosis in human adults. In one year, the number of cell divisions and deaths that occur in a person's body reaches approximately equal to the weight that person.

Balance (homeostasis) is achieved when the rate of mitosis (cell division) on the network unmatched by cell death. When this balance is disturbed, one of the following will happen:

  • When the speed of cell division is higher than the rate of cell death, will form tumors
  • When the speed of cell division is lower than the rate of cell death, will occur due to lack cell disease.

Both of these conditions can be fatal or highly damaging.

Source from: Wikipedia

0 komentar:

Post a Comment

Followers

 
Copyright © 2011 About Mutation | Themes by Muta-Tion.