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

Blackquarter, B l ac k q u ar t e r The disease is otherwise k...

B l ac k q u ar t e r The disease is otherwise known as black leg or emphysematous gangrene, and it is associated with severe toxaemia, emphysematous swelling of muscl

What are the benefits of soil testing, What are the benefits of Soil testin...

What are the benefits of Soil testing Soil testing is done to assess the nutrient supplying capacity of the soil. The data obtained as a result of  testing is useful for recom

What are the three main parts of a eukaryotic cell, Q. What are the three m...

Q. What are the three main parts of a eukaryotic cell? The eukaryotic cell can be separated into two major portions: the cell membrane that separates the intracellular space fr

Brain thinking, in what form brain stores thinking or past experiences?

in what form brain stores thinking or past experiences?

What is genetic equilibrium, What is genetic equilibrium? The Genetic e...

What is genetic equilibrium? The Genetic equilibrium is the result of the Hardy-Weinberg law, a principle that affirms that under specific conditions the frequencies of the all

Explain natural history of mitral stenosis, Q. Explain Natural History of M...

Q. Explain Natural History of Mitral Stenosis ? Untreated, mitral stenosis is a serious disease with observed 10-year mortality of 70-80 per cent in sy

Explain the stages of alzheimer''s disease, Explain the Stages of alzheimer...

Explain the Stages of alzheimer's disease? Stage I - There is an increased forgetfulness, anxiety and depression. Associated nutrition related changes include difficulty in

Risk analysis- definiton of food, Risk analysis- Definiton of Food Food...

Risk analysis- Definiton of Food Food  :  Any  substance,  whether processed,  semi- processed  or  raw  which  is intended for human consumption, containing drinks, chewing gu

What are herbicide tolerant crops in ecological, What are Herbicide toleran...

What are Herbicide tolerant crops in ecological Herbicide tolerant crops (HTC)  Ecological  a)  Increased use of the herbicides that plant is  tolerant to (describes ecologi

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