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

Major events during gastrulation, MAJOR EVENTS DURING GASTRULATION - 1....

MAJOR EVENTS DURING GASTRULATION - 1.       There is rearrangement of cells due to morphogenetic movement of the cells of blastoderm. 2.       The three primary germ layer g

List out the different preservation techniques, List out the Different Pres...

List out the Different Preservation Techniques? The different preservation techniques commonly used today are given in the Table. Table: Methods of food preservation a)

What are the euchromatin and heterochromatin, Q. What are the euchromatin a...

Q. What are the euchromatin and heterochromatin? Chromatin is uncondensed nuclear the DNA the typical DNA morphology in interphase the phase of the cell cycle in which the cell

Explain microorganisms associated with the raw foods, Explain Microorganism...

Explain Microorganisms Associated With The Raw Foods? Foods of animal and plant origin are in direct contact with air, soil and water and get contaminated with the microorganis

Define proteins in the immune system, Define Proteins in the immune system?...

Define Proteins in the immune system? Proteins such as γ-globulin serve to protect the body against foreign cells. The immunoglobulin produced by lymphocytes is the large polyp

Which aqueous solution has the lowest ph, The aqueous solution with the low...

The aqueous solution with the lowest pH is: Select one: a. 0.01 M HCl. b. 0.1 M acetic acid (pKa = 4.86). c. 0.1 M formic acid (pKa = 3.75). d. 0.1 M HCl. e. 10 t

Bacterial motility, What morphological structure is responsible for bacteri...

What morphological structure is responsible for bacterial motility?

In what form is most carbohydrate taken in the normal diet, In what form is...

In what form is most carbohydrate taken in the normal diet? Most carbohydrate is taken normal diet in as starch.

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