Differentiation of tissues - root apex, Biology

Differentiation of Tissues - Root Apex

New cells generated from the divisions of meristematic cells start expanding and differentiating further. Epidermis, cortex and stele are formed. Stele is organized into xylem forming a star shaped central axis with columns of phloem between the points of the star, encircled by the pericycle. But what are the processes that control differentiation? Certain experimental studies involving surgical removal of small portion of root tips and observing their differentiation in culture has thrown much light on root development. Smaller pieces while differentiating produced monoarch and diarch type vascular organisation even though originally the plant root showed triarch pattern. This experiment indicates that a definite size of root tip is needed for realization of its full morphogenetic potential. But on further growth even these small pieces revert back to normal pattern of organisation of vasculature. If auxin at 10-5 M concentrations was provided in the culture exarch vascular tissue was formed. The ontogenic development of the primary vascular system of the root is simple.

The differentiation of the root tissues behind the apical meristems is summarized as follows: Periclinal divisions in the cortex cease near the level where the sieve elements mature: beyond this region the root undergoes rapid elongation and the maturation of the protoxylem usually takes place when the process of elongation is almost completed: Casparian strips develop in the endodermal cells before the maturation of the protoxylem elements and also before the appearance of root hairs. Phytohormones influence the development of secondary vascular tissue. When the roots are cultured on a nutrient medium containing Indole Acetic Acid (10-5 m) along with sucrose can induce secondary vascular tissue. Cytokinins and hexitols in small amounts promote secondary vascular tissue. Roots also depend upon vitamin 'B' for their proper growth.

Posted Date: 1/24/2013 1:16:46 AM | Location : United States







Related Discussions:- Differentiation of tissues - root apex, Assignment Help, Ask Question on Differentiation of tissues - root apex, Get Answer, Expert's Help, Differentiation of tissues - root apex Discussions

Write discussion on Differentiation of tissues - root apex
Your posts are moderated
Related Questions
Q. What is Aprecise diagnosis? Aprecise diagnosis is necessary to establish the mode of therapy. Patients with initial blood phenylketonuria level of 121 m moll1 (> 2 mg/dl) sh

Q. What is the main nitrogen waste of humans? Human beings excrete largely urea eliminated with the urine.

Explain about the Glycoproteins? Most of the naturally occurring conjugated proteins are glycoproteins. Sugar molecules are covalently bound to them, especially those secreted

What are the alleles of a gene? The Diploid individuals have paired chromosomes. For instance in humans there are 23 pairs of chromosomes totaling 46 chromosomes. Every pair co

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

Aim of Diabetes Counselling Diabetes is a life-long illness. Diagnosis of diabetes has psychological and physical implications. Preventive counselling and life style change ca

The marine biomes consist of the earth's oceans and its associated areas like the shorelines, islands, reefs and estuaries. The marine waters contain about 3.5 percent salt, mostly

What factors lead to spoilage of fish flesh? A difference in the composition of tissues among different species, climate, procurement and holding practices are amongst few of

You have to do counselling of a diabetic patient and the family members when you are working in a diabetic clinic or community setting in health center. To be an effective counsell

Q. Explain Uristix Benedicts test? No sugar/glucose is excreted in the urine in normal individuals. In diabetics, glucose is excreted by the kidneys when the blood sugar levels