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

Blood flow, if i start in the superior mesenteric vain where do i have to g...

if i start in the superior mesenteric vain where do i have to go through to get to the left anterior circumflex humeral artery. by the way of the hepatic portal vein and the heart

Describe the significance of micronucleus., Describe the significance of mi...

Describe the significance of micronucleus. One of two types of dimorphic nuclei found in ciliate protozoans. The single micronucleus contains only one copy of the genome and is

Zoonoses disease-monkey b virus disease, Monkey B virus disease The di...

Monkey B virus disease The disease is caused by Herpesvirus simiae or B virus, a member of the herpes group of viruses. The infection occurs naturally among primates of the ge

Explain free water - water found in food, Explain Free Water - Water Found ...

Explain Free Water - Water Found in Food? Water which is bound by such minute forces, that its vapour pressure is equal to the vapour pressure of pure water. It can be found as

Explain ventricular septal defect in details, Explain Ventricular Septal De...

Explain Ventricular Septal Defect in details ? Indications of surgery :  Some VSDs close spontaneously or become smaller in size. This has to be taken into consideratio

What are the near point and the far point of the vision, What are the near ...

What are the near point and the far point of the vision? The near point is the closest distance among an object and the eye that makes possible the formed image to be focused,

Explain carboxypeptidase, Carboxypeptidase The  inactive  zymogen  proc...

Carboxypeptidase The  inactive  zymogen  procarboxypeptidase  is  activated  by  trypsin .The further action on the polypeptides is carried out by carboxypeptidase which  attac

Describe components of a complete diagnosis, Describe Components of a Compl...

Describe Components of a Complete Diagnosis of Congenital Heart Disease ? A complete diagnosis of congenital heart disease requires accurate and thorough description of the he

Define distant osteogenesis, Q. Define Distant Osteogenesis? Distant Os...

Q. Define Distant Osteogenesis? Distant Osteogenesis : This type of healing has also been described to explain the phenomenon of "Osseointegration" of machined metallic implant

Assessment of new born - purposes and precautions, Assessment of new born ...

Assessment of new born The main purposes are: i) To identify normal characteristics in the neonate ii) To identify existing abnormalities, ii any iii) To carry

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