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.
Improper fit at the abutment/- implant interface It is very vital that the fit of the abutment is crosschecked radiographically prior to final delivery of the prosthesis. The m
functions of arteries in mammals
what is diffusion
Sertoli cells are found in: 1. ovaries and secrete progesterone 2. adrenal cortex and secrete adrenaline 3. seminiferous tubules and provide nutrition to germ cells 4.
what are the disadvantages of protozoa?
Why are euglenas involved in polemics related to their taxonomic classification? Euglenas are included in taxonomic polemics because they tend to be classified sometimes as pro
Explain the s1M filament theory of muscle contraction. What is special of "FlavrSavr" variety of tomato? Why is it preferred to its normal native variety? Illustrate a label
examples of autotrophic nutrition
Match dehydration reaction and hydrolysis reaction to molecule synthesis and molecule break-down.
What is Surviving Implants It is a term described by Albrektsson that applies to implants that are still in function but have not been tested against success criteria. Such as
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