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

Illustrate the removal of carbon dioxide from the body, Which of the follow...

Which of the following processes in capillaries in the lung assist in the removal of carbon dioxide from the body? A. Net flux of carbon dioxide from red blood cells into plasm

Determine about the multicellular organisms, Another possible way to classi...

Another possible way to classify organisms would be to separate them into unicellular and multicellular organisms. Explain why this is not a useful classification system. Other

Define categories of fatty acids, Define Categories of Fatty Acids? The...

Define Categories of Fatty Acids? The fatty acids can be discussed under following heads: Saturated and Unsaturated, Short chain, medium chain and long chain,

Cnidaria and protozoan, What are the advancement of cnidaria over protozoa

What are the advancement of cnidaria over protozoa

Explain the meaning of anthropometric measures, Explain the Meaning of anth...

Explain the Meaning of anthropometric measures Anthropometric Measures mean and its uses. The term Anthropometric refers comparative measurement relating to the body structure.

Explain the mechanisms of endosseous integration, Mechanisms Of Endosseous ...

Mechanisms Of Endosseous Integration Three terms may be used to describe individual aspects of bone formation process that can occur around implants. They are Osteoconduction,

Determine the nutritional needs of humans, Determine the nutritional needs ...

Determine the nutritional needs of humans? In the previous unit, we saw how involvement in sport or vigorous activities can affect the body's nutrient needs. In this unit, we w

Geothermal energy, It is that energy which lies, embedded within earth's cr...

It is that energy which lies, embedded within earth's crust. In some places heated water comes out through the surface of earth as hot spring or steams. This hot geothermal water o

Explain genetically modified foods, Normal 0 false false fa...

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

What is meant by gene expression, What is meant by Gene Expression? The...

What is meant by Gene Expression? The synthesis of protein under the influence of gene is called Gene Expression. All human cells are derived from a single cell, fertilized egg

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