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

What are the digestive functions of the liver, Q. What are the digestive fu...

Q. What are the digestive functions of the liver? The liver has other digestive functions, besides making bile for release in the duodenum. The venous network that absorbs n

Explaintransketolase, ExplainTransketolase Transketolase with the help...

ExplainTransketolase Transketolase with the help of TPP  and Mg ++   is  required again. This  time  it  transfers carbon 1+2 from xylulose-5-phosphate  to erythrose-4-phospha

Explain the transfer from liquid medium to solid media, Explain the Transfe...

Explain the Transfer from liquid medium to solid media? Here the steps involved include: 1. Inoculating loop is sterilized by incineration and allowed to cool, as described

Is neuron b in the frog central nervous system, IS Neuron B in the frog cen...

IS Neuron B in the frog central nervous system Consider Neuron B in the frog central nervous system whose plasma membrane has a previously unknown channel that is selectly cond

Origin of plastid, ORIGIN (1) From Pro plastid (2) Division (3) E...

ORIGIN (1) From Pro plastid (2) Division (3) Endosymbiotic origin from a cyanobacterium

Build a genomic dna library, Construct a genomic DNA library with the help...

Construct a genomic DNA library with the help of some methylaee and finall do viral packaging.

Classify the diversity of organism in different groups, Q. Classify the div...

Q. Classify the diversity of organism in different groups • The goal of taxonomy is to develop a workable classification that reflects evolutionary relationships and provides

Difference between spermatogenesis and oogenesis, DIFFERENC E BETWEEN SPER...

DIFFERENC E BETWEEN SPERMATOGENESIS AND OOGENESIS - S.NO . SPERM A T OGENESIS OOGENESIS 1.   2.   3.

Explain poor growth - clinical signs of kwashiorkor, Explain Poor growth - ...

Explain Poor growth - clinical signs of kwashiorkor? Growth retardation is the earliest manifestation of kwashiorkor, the child will be lighter and shorter than its normal peer

What is the meaning of reitan''s program, What is the meaning of Reitan's p...

What is the meaning of Reitan's program Reitan's program can be conceptualised as an effort to demonstrate the usefulness nad accuracy of Halstead's tests and related procedure

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