Induction of mesoderm in amphibians, Biology

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.

Posted Date: 1/29/2013 12:23:32 AM | Location : United States

Related Discussions:- Induction of mesoderm in amphibians, Assignment Help, Ask Question on Induction of mesoderm in amphibians, Get Answer, Expert's Help, Induction of mesoderm in amphibians Discussions

Write discussion on Induction of mesoderm in amphibians
Your posts are moderated
Related Questions
what two gases are released by animals during the process of cellular respiration

What does a two-direction arrow show in a chemical equation? The oxygen atoms share two pairs of electrons, as every atom needs two more electrons to fill the orbitals of its o

Human Development Human development is a continuous procedure that begins when the ovum from a female is fertilised via sperm from a male to form the zygote. Growth and differ

What are bacteria? Bacteria are unicellular and prokaryotic beings. Bacteria have simple organization; they present an , plasma membrane, external cell wall, circular DNA withi

Q. Etiology of constipation? The etiology and management of two distinct disorders of the bowel viz., diarrhoea and constipation. We small continue our discussion on certain ot

what is the advantage of being dark skinned?

IsoniazidĀ  Serum aminotransferase activity increases in 10% to 20% of patients taking isoniazid, especially in the early weeks of treatment, but often returns to normal even wh

LAN LAN stands for Local Area Network. This kind of network consists of a set of interconnected computers that are not geographically spread out over a large area. For exa

Explain Endocarditis The risk of endocarditis is considered high in patients with last bacterial endocarditis, prosthetic heart valves, complex cyanotic congenital heart diseas

briefly explain pinocytosis