Differentiation of tissues - root apex, Biology

Assignment Help:

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.


Related Discussions:- Differentiation of tissues - root apex

LIFE PROCESSES, WHAT IS HEART? AND WHAT THEY DO WORK IN OUR BODY.

WHAT IS HEART? AND WHAT THEY DO WORK IN OUR BODY.

What is the general function of leukocytes, Q. What is the general function...

Q. What is the general function of leukocytes? What are leukopenia and leukocytosis? The general function of leukocytes is to participate in the made inside the body or defense

Explain about coping mechanism, Q. Explain about Coping mechanism? Copi...

Q. Explain about Coping mechanism? Coping mechanism is defined as the skill used to reduce stress. In other words, these are consciously used skills. Overuse of coping mecha

How are amphibians characterized, Q. Amphibian identity card. How are amphi...

Q. Amphibian identity card. How are amphibians characterized according to examples of representing beings, basic morphology, circulation, skin, nitrogen waste, respiration, thermal

Importance of inherited characteristics in their explanation, QUESTION ...

QUESTION Behaviourists underestimate the importance of biological factors such as the inherited factors, by emphasizing the simple approach of Stimulus-Response to explain beha

Determine the goal of a bcc programme, Determine the Goal of a BCC Programm...

Determine the Goal of a BCC Programme The overall goal of BCC programs for diabetes mellitus is to promote behaviors that control blood sugar and prevent complications. Thes

State the phases of soil genesis, State the phases of soil genesis Soil...

State the phases of soil genesis Soil genesis embodies two distinct phases. One is weathering that involves disintegration and decomposition of rocks and minerals, the other is

Oxidation reduction potential, what exactly is oxidation and reduction pote...

what exactly is oxidation and reduction potential and how its an imp. factor in spoiling meat

Name the endocytosis, Name the endocytosis?   A.  During endocytosis of...

Name the endocytosis?   A.  During endocytosis of GLUT4 transporters in fat cells, there is removal of GLUT4 transporters from plasma membranes.   B.  During endocytosis of

Evolution and scope of dental implantology, The need to replace missing tee...

The need to replace missing teeth has haunted humans for time immemorial. Since antiquity man has attempted to solve the problems associated with failing dentition. The goal of mod

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