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!
Induction of Mesoderm in Amphibians
Earlier you know that an event that precedes neural ectoderm induction in amphibians is the induction of mesoderm. Until 32 cell stage in amphibian blastulae there are only two cell sorts. In animal hemisphere there are small ectodermal cells and in the vegetal hemisphere there are large endodermal cells. A third cell type from which mesoderm develops is made in the equatorial region of the embryo throughout early blastula stage.
Fate map of Xenopus embryo reveals that equatorial cells in contact with both of the animal and vegetal cells in the equator of blastula are precursors of mesoderm. How is the fate of the equatorial cells as prospective mesoderm cells determined? Either the ooplasmic determinants like intrinsic factors or cell interactions as extrinsic factors may play a role in such type of a determination. To test one of the two probabilities, the blastulae were divided into explants of animal, equatorial and vegetal cells and cultured independently. Animal cells that are developed into ectoderm cells, vegetal cells into endoderm cells and the equatorial cells into mesoderm cells. Though, if the animal cells were recombined with vegetal cells and cultured, they formed mesoderm cells also suggesting the probability that mesoderm formation is not exclusively dependent on ooplasmic determinants. The equatorial cells develop into mesoderm cells possibly since the adjacent vegetal cells secrete some inducing substance which influences the adjacent cells of the equatorial region inducing them to become mesodermal cells. In the general blastula, the animal hemisphere cells differentiate only into ectoderm since they are widely separated from the vegetal cells by the blastocoel and thus are too far from the source of inducer.
Q. What do you mean by Current Impediments? Given the impressive list of past achievements, we expect that quantitative process to biological problems will continue to repay us
A pure phospholipid bilayer with its hydrophobic interior, is permeable to water and gases such as O2, CO2, N2 and small uncharged polar molecules such as urea, ethanol, bu
Procaryotic Structure and Diversity The first organisms which did not have well defined nucleus, called procaryotes, (pro = earlier, caryon = nucleus) were probably anaerobic a
Define Factors Influencing RS Content of Foods? Different fractions of RS mentioned in Table may be naturally present in some foods or may be generated as a result of industria
Explain some Effect of Inadequate nutrition? Inadequate nutrition ranks as one of the major problems of old age. Various factors which may be responsible for the change in one
Explain about the Obliques muscles The superior and inferior oblique muscles form an angle of about 51 0 with the optical axis. The oblique muscles produce cyclorotation becau
Determine the types of symbols used in Soil Horizons Three kinds of symbols are used in various combinations to designate horizons. These are capital letters, lower case lett
At the end of the ventricular contraction, maximum arterial pressure is attained and blood flow is most rapid. This is correctly termed the: a) Arterial maximum b) Diastolic
Explain the Composition of Nutrient Agar and Nutrient Broth? The composition and procedure for preparation of some commonly used media, which we will use in the laboratory for
Q. How is the cooling of tissues and organs for medical transplants associated with the effect of temperature upon enzymatic reactions? The molecular degradation during the dec
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