Gastrulation in amphibians, Biology

Assignment Help:

Gastrulation in Amphibians

Amphibians comprise a large and moderately telolecithal egg. Cleavage is holoblastic and unequal generating a spherical blastula along with a reduced eccentric blastocoel shifted towards the animal pole. The blastocoel has a thin roof of various layers of small yolk-poor cells and a floor of large yolk-laden cells various layers deep extending down to the vegetal pole. The procedure of gastrulation starting with such a blastula is complicated since it is impossible for the enormous mass of large yolk cells in the floor of the reduced blastocoel of the cells to invaginate from the vegetal pole inwards as takes place in sea urchin. In place, invagination begins on the future dorsal side of the embryo where cells are small and less yolky. Furthermore, invagination is very limited and only initiates gastrulation; rest of the gastrulation process involves a variety of cell movements involving convergence, divergence.


Related Discussions:- Gastrulation in amphibians

Urology., what is the effect of KClO4 on the kidneys in the nephrotic syste...

what is the effect of KClO4 on the kidneys in the nephrotic system?

Sharps-hazards in biology laboratory, SHARPS : Cuts due to careless handli...

SHARPS : Cuts due to careless handling of sharps such as sectioning razors, microtome blades etc. are probably the most common cause of injury in the biology lab. The only real re

Explain in brief about polymers, Explain in brief about Polymers In com...

Explain in brief about Polymers In comparison to metals and ceramics, polymers are weak and flexible. These are not popular as dental implant materials. Examples of polymeric m

Which of structures is the nuclear membrane composed, Q. which of structure...

Q. which of structures is the nuclear membrane composed? Eukaryotic cells have nucleus delimited with two juxtaposed membranes that continue with the membrane of the endoplasmi

Define obligatory nitrogen losses, Define Obligatory Nitrogen losses? T...

Define Obligatory Nitrogen losses? The Committee estimated the total obligatory nitrogen losses through faeces, urine, skin and other miscellaneous routes in adult men as 2.0 m

Define drawbacks for underwater weighing method, Define drawbacks for under...

Define drawbacks for underwater weighing method? Since the major drawbacks with UWW method are that the subject needs to be totally submerged underwater and exhale all of the a

#title.zoology., #question.why obelia is considered of special interest in ...

#question.why obelia is considered of special interest in zoology.

Define about the polyphenols, Define about the Polyphenols? We now come...

Define about the Polyphenols? We now come to a group of compounds, which were until recently considered to adversely influence nutrient absorption or giving colour to foods e.g

Define essentiality of nitrogen for growth of micro-organism, Define Essent...

Define Essentiality of Nitrogen for Growth of Micro-Organism? Nitrogen is an essential atom in certain cellular macromolecules, e.g. amino acids, purines, pyrimidines, enzymes,

Bio212, do you think the social and cultural environment of the 18th and 19...

do you think the social and cultural environment of the 18th and 19th centuries helped or hindered the study of microbiology in particular and science in general

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