Meroblastic or partial cleavage, Biology

Assignment Help:

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.


Related Discussions:- Meroblastic or partial cleavage

List the goals of targeting blood pressure in diabetics, List the goals of ...

List the goals of targeting blood pressure in diabetics. Goals of targeting blood pressure in diabetics are:  Patients with diabetes should be treated to a systolic blood pr

In which way bacteria and the archaea different, How are the bacteria and t...

How are the bacteria and the archaea different from all the other cellular microbes? -They have cell walls? -They can move? -They reproduce asexually? -They have no nucleus?

Sources of food contamination, All plants and animals have a natural microf...

All plants and animals have a natural microflora associated with them. For example, the plants have a natural microflora associated with the surface of roots, stems, leaves e

What are the specialized structures help adhesion cell, What are the specia...

What are the specialized structures that help the adhesion between cells? The structures responsible for the union of the epithelial cells are known as cell junctions. The main

Heart and lungs, what are the main functions of lungs and heart

what are the main functions of lungs and heart

Illustrate the methods to evaluate osseointegration, Q. Illustrate the Meth...

Q. Illustrate the Methods to evaluate osseointegration? The criteria of success in implant dentistry remains complex. The vast majority of clinical reports noting success and f

What is intermediate acting insulin, Q. What is Intermediate acting insulin...

Q. What is Intermediate acting insulin? Intermediate acting: This type works more slowly than short acting. It works hardest 8-12 hours after injection and still keeps on worki

What determines an individual''s work capacity, What determines an individu...

What determines an individual's Work Capacity or VO 2 Max? Both aerobic and anaerobic mechanisms determine an individual's performance capacity. VO 2 max is determined by the

Deficency diseases and metabolic disorders, Deficency Diseases and Metaboli...

Deficency Diseases and Metabolic Disorders Nutrients required for life sustenance are grouped into 6 basic classes, viz. water, carbohydrates, proteins, fats, minerals and vita

Historic example of evolutionary quantitative geneticists, Define Historic ...

Define Historic Example of Evolutionary quantitative geneticists? Evolutionary quantitative geneticists have developed tools to create predictions about the short-range evoluti

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