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
DISACCHARIDES They are oligosaccharides composed of two monosaccharide residues . Three common disaccharides are    sucrose (glucose + fructose) = cane suger maltose

What is Bone grafting The detailed description of the graft materials ranging from alloplastic, xenograft, allograft and autogenous grafts;  including their choice has been dis

Minerals and reproduction The mechanism of mineral-reproduction interactions is not fully understood because  of the complexity of neuro-hormonal dialogue. Some minerals act direc

Differences between cells of Prokaryotes and Eukaryotes The prokaryotes also differ from the eukaryotes in many other ways, as you can see from Table. Table: Differences

Q. What are the major biological functions in which chlorine ions participate? Like sodium cations, chlorine anions actively participate in the regulation of the osmolarity of

Name the system that contains three neurons Consider a system that contains three neurons in a culture dish bathed in normal physiological saline.  All three neurons are health

Testing for urine sugars is not recommended for either diagnosis or monitoring of patients with diabetes. This is because a urine sugar is not a reliable test. When no facilities a

1.How does the skin on your palm differ from that on the back (posterior) of your hand? 2.Describe the differences observed in the type and distribution of hair on the front (anter

why do ecological models commonly have limited applications ?

Explain briefly about Foams   Consider the following example. Take some liquid in a glass and agitate or shake it vigorously. What do you observe at the top of the liquid. Yes,