Totipotency and pluripotency, Biology

Assignment Help:

Totipotency and Pluripotency

In the starting we said that the fertilized egg cell (zygote) has the capacity or potentiality to give rise to all kinds of cell types, like a blood cell or a bone cell or a muscle cell etc. In embryological terminology such a cell is said to be totipotent. The zygote cleaves and makes a large number of blastomeres. The blastomeres may as well remain totipotent up to a certain stage and have the capacity to form every cell type of the organism. Though, as development proceeds the various blastomeres lose totipotency but may still be pluripotent. By pluripotent it is meant that they are able to make several but not all of the various cell types or tissues. Ultimately, with further development, even the pluripotency is lost and different groups of cells of the embryo are now capable of forming only one particular cell type or tissue.

For instance, up to a certain stage of embryonic development prospective ectodermal cells can make either epidermis or neural tissue, i.e. they are pluripotent. But at a later stage cells of one region of ectoderm can make only epidermal tissue and those of another region can distinguish only into neural tissue. What may be the cause of progressive restriction of potency in diverse embryonic cells although they are all descendents of the same single cell, zygote? Each one of these embryonic cells contains a nucleus which is also the descendent of similar zygotic nucleus. Does the restriction in potency in several embryonic cells result from differential distribution of specific cytoplasmic substances between different blastomeres during cleavage of zygote and subsequent divisions? We may ask a identical question with regards to the nucleus which contains the genes that direct the differentiation into specific tissues and cells types.


Related Discussions:- Totipotency and pluripotency

Question 1, Which type of reproductive structure has a better chance of sur...

Which type of reproductive structure has a better chance of survival if there was a sudden temperature change in its environment? A.)asci B.)zygosporangium C.)basidium D.)lichen

Permeability, Permeability Permeability is the ability of a soil to tra...

Permeability Permeability is the ability of a soil to transmit water or air. Permeability or infiltration rate is measured in terms of the rate of water flow through the soil i

State the foot examination of a diabetic patient, State the Foot examinatio...

State the Foot examination of a diabetic patient Foot examination of a diabetic patient is very crucial in early detection and proper treatment of foot problems.  In every fol

Assessment of diastdlic function, Q. Assessment of Diastdlic Function? ...

Q. Assessment of Diastdlic Function? Myocardial ischemia Clters diastolic function of left ventricle. The earliest abnormality to appear with prolonged ischemia is delayed my

Why does not gene therapy cure cystic fibrosis, Why doesn't gene therapy cu...

Why doesn't gene therapy cure cystic fibrosis? Although a normal gene is introduced into a patient's surface cells in the lung, these cells are not the ones that require produc

Hemoglobins - process of respiration, Hemoglobins - Process of Respiration ...

Hemoglobins - Process of Respiration Hemoglobins are the very well known of all respiratory pigments. The basic molecular unit of Hemoglobin contains a haem group bound to a

The rate of germination, You are asked to set up an experiment to investiga...

You are asked to set up an experiment to investigate the effect of temperature on the rate of germination. You place ten soaked peas in every of three flower pots containing moist

Solubility of oxygen, Solubility of Oxygen It is also important to kno...

Solubility of Oxygen It is also important to know that solubility of gases decreases with the presence of solutes or increased salinity. Table shows the solubility of oxygen a

Define dietary goals in parkinson''s disease, Define Dietary Goals in Parki...

Define Dietary Goals in Parkinson's Disease? The main goals include: - Maintain desirable weight - Promote absorption of anti- Parkinson's drug levodopa - Lessen swall

Explain classification of lipids, Classification of lipids  A general c...

Classification of lipids  A general classification of lipids based on their structural components is presented in table. Such a classification, however, is possibly too rigid f

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