Meroblastic or partial cleavage, Biology

Meroblastic or partial cleavage

The egg does not divide totally because divisions are restricted to only a part of the egg where as the rest of the egg remains completely uncleaved. It is of two types:

A. Discoidal meroblastic cleavage: It occurs in the heavily yoked macrolecithal and highly telolecithal eggs, as for instance in cephalopod molluscs, reptiles, birds and monotremes (egg laying mammals). The cleavage is restricted to the cytoplasmic germinal disc located at the animal pole. Even the germinal disc divides incompletely where as the entire yolk mass remains undivided.

B. Superficial meroblastic cleavage: This takes place in the centrolecithal eggs of insects. Cell divisions are restricted to the peripheral cytoplasmic layer whereas the centrally located yolky is left undivided.

Posted Date: 1/25/2013 1:28:27 AM | Location : United States







Related Discussions:- Meroblastic or partial cleavage, Assignment Help, Ask Question on Meroblastic or partial cleavage, Get Answer, Expert's Help, Meroblastic or partial cleavage Discussions

Write discussion on Meroblastic or partial cleavage
Your posts are moderated
Related Questions
Determine the term - Test-retest reliabilities The test manual reports reliability data. Test-retest reliabilities for the 13 main scales range from .78 to .96. The problem of

Define the Features of Phylum Nematoda? Phylum characteristics of Nematoda which are the world's most abundant multicellular organisms are as follows: 1. Nematodes occur in

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

In a Population that is in Hardy-Weinberg equilibrium, the frequency of the recessive Homozygous genotype is 0.49. The frequency of individuals Homozygous for the Dominant allele i

CHITIN It is polymer of N-acetyl-D-glucosamine. It is a structural homopolysaccharide found in the fungal walls as fungus cellulose and as chitin in the exoskeleton of

Q. What do you mean by Hemichordata ? Hemichordates re vermiform (worm-like) animals which have few characters like those of the chordates, hence the name hemichordata (hemi :

What is Thermoregulation in Cold? Heat production parallels the increase in O 2 uptake, the magnitude of which depends on the muscle mass .engaged in slivering or work and the

Q. What is the cell theory? Cell theory asserts that the cell is the element unit of living beings. Before the discovery of the cell, it was not acknowledged that living bei

What is the excretory organ of an agama lizard?

Q. What is the gas exchange unit of the mammalian lungs? The gas exchange units of the mammalian lungs are the alveoli. Q. What is the physical process through which gas ex