Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Hepatitis A Hepatitis A vaccine (Havrix - GlaxoSmithKline; Vaqta Merck) is recommended for all susceptible travelers going anywhere other than Canada, Australia, New Zealand,
The citric acid cycle functions in the mitochondria of eukaryotes and in the cytosol of prokaryotes. The Succinate dehydrogenase, the only membrane-bound enzyme in t
A normal healthy cell is bathed in a normal extracellular saline. The plasma membrane of the cell contains voltage-gated sodium channels, sodium-glucose co-transporters, and sodiu
(1) The 7,893 bp plasmid shown below was digested with a series of restriction enzymes (P = PstI, B = BamHI, S = SalI, X = XbaI). Answer the questions below. a) Indicate
VERTEBR A T A It is divided into two parts - 1. Agnetha 2. Gnetha S.No. C haracter A gnetha G
How are mutagenic agents related to cancer incidence in a population? Is cancer a disease transmitted to the individual offspring? The exposition of a population to mutagenic a
why is it known as middle man
Microtubule assembly: A) generally originates in the centrosome. B) Occurs only during mitosis. C) Occurs randomly throughout the cell. D) Is regulated by myosin. E) Is inhibited d
As a result of mutarotation, D-glucose exists in all of the following forms EXCEPT: Select one: a. L-glucopyranose. b. alpha-anomer. c. free aldehyde (linear) d. bet
Classification of proteins based on chemical properties? Depending on their chemical properties and optical activity, the amino acids in proteins are classified under the follo
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd