Iaa stimulates cell enlargement, Biology

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.

Posted Date: 1/24/2013 2:33:54 AM | Location : United States







Related Discussions:- Iaa stimulates cell enlargement, Assignment Help, Ask Question on Iaa stimulates cell enlargement, Get Answer, Expert's Help, Iaa stimulates cell enlargement Discussions

Write discussion on Iaa stimulates cell enlargement
Your posts are moderated
Related Questions
Aerotolerant anaerobes are incapable of aerobic respiration, but can nevertheless grow in the presence of air. Many lactic acid bacteria fall into this category. They can only gene

A decrease in parasympathetic discharge to the heart leads to A. an increase in the conductance of F-channels in SA node cells. B. a decrease in the conductance of potassium

Define tracheal system in details. Respiratory system found in insects and some spiders where air passes directly to the tissues through a series of tubules. Since oxygen tran


S i m p l e indigestion The disease is common in stall-fed individuals. Consumption of indigestible food material, moldy and nutritionally unbalanced feed results in simpl

Corpus Allatum and Prothoracic Gland Corpus Allatum The corpus allatum is situated in the neck region of insects. It is generally a rounded, solid and translucent struc

Q. Advantage and Disadvantage of steam sterilization? Advantage: most efficient and reliable sterilization method available. Its quite simple to operate and relatively inexpens

Auxins The history of discovery of auxin is a fascinating chapter in plant physiology. The hormone auxin was discovered first, through some elegant experiments by Charles Darw

VACUOLES  Some animals cells may have  one to a few small  fluid  filled vacuoles.. Plants  cells  in general  possess one or a few  large vacuoles. Vacuoles  of animals  cells

What are the main constituents of the earth's atmosphere in our time? The present atmosphere of the earth is constituted mostly of molecular nitrogen (N2) and molecular oxygen