Iaa stimulates cell enlargement, Biology

Assignment Help:

IAA Stimulates Cell Enlargement

Cell wall contains layer of cellulose fibrils and are normally quite rigid. Thus for a cell to grow, there must be a mechanism for relaxing the cellulose fibrils. IAA releases the cross linking bands which hold the micro fibrils together. Auxin is thought to cause the walls to become plastic and them osmotic water intake causes the cell to swell like a balloon. American physiologist P.M. Ray has observed that IAA effect on elongation begins after a lag period of only 8-12 minutes, in tissues as coleoptiles. Recently it has been found that with certain auxins or even with IAA itself when used under correct conditions, the lag period can be reduced to 1 minute or less.

These effects are now considered to be as a result of activisation of proton pumps in membrane that pump protons in cell wall and cause a rise in acidity. Acidification loosens bonds in cell wall and cell wall plasticity increases. This rapid response is followed by activation of m-RNA translated into enzymes that catalyze synthesis of cellulose and other cell wall materials which cause the strengthening of elongated cell wall completing the cell elongation.


Related Discussions:- Iaa stimulates cell enlargement

Phylum coelenterata, #questioen..what is the example of outline og phylum c...

#questioen..what is the example of outline og phylum coelenterata

Explain the term kwashiorkor, Explain the term Kwashiorkor? The term Kw...

Explain the term Kwashiorkor? The term Kwashiorkor means the 'disease the first child gets when the second baby is born', that is, 'the sickness of the deposed child'. Thus, th

Growth charts, Growth Charts Management alone without any standard of ...

Growth Charts Management alone without any standard of comparison do not serve useful purpose. A number of standards have been developed to compare the measurement of any

How to investigate mitral regurgitation by chest radiogram, Q. How to inves...

Q. How to investigate mitral regurgitation by Chest Radiogram? Enlarged left atrium is obvious on chest X-ray and it may occupy most of the cardiac silhouette in patients with

Explain the results of coarctation of aorta, Explain the Results of Coarcta...

Explain the Results of Coarctation of Aorta? Early hospital death in isolated coarctation is around 2 to 10 per cent. In many reports, mortality for older babies approaches 0.

Explain complete and incomplete digestive system , Normal 0 fal...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Mineralisation and humification-formation of soil, Mineralisation and Humif...

Mineralisation and Humification As a result of physical weathering, the rocks are broken down into smaller particles. But this is not the true soil, and plants cannot grow well

Explain about the optic disc, Explain about the optic disc The optic di...

Explain about the optic disc The optic disc is also called a blind spot while the macula is referred to as the yellow spot. The ora serrata (the intersection between the retina

Lampbrush chromosomes, LAMPBRUS H CHROMOSOMES Discovered by Rucker...

LAMPBRUS H CHROMOSOMES Discovered by Ruckert . Lampbrush Chromosomes were seen in Oocytes of several different animals like shark, amphibians, reptiles and birds. (Most

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