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

Which keel is characteristic of the flowers, Keel is characteristic of the...

Keel is characteristic of the flowers of : 1. Gulmohur 2. Cassia 3. Calotropis 4.  Bean Bean

Calculate concentration of solution from standard curve, Calculate the Conc...

Calculate the Concentration of Unknown Solution from Standard Curve? i) First take different volume of standard solution (say 0.2, 0.4, 0.6, 0.8, 1.0 ml) and then calculate the

Erythema - common disorders of skin, Erythema: Erythema is one of  the...

Erythema: Erythema is one of  the,commonest primary lesions of  the skin. It  is produced by  the dilation of the cutaneous blood vessels.  If the dilation  is accompanied  by

How to use atp to make reactions go, What do enzymes do, and how? How is en...

What do enzymes do, and how? How is enzyme activity regulated in cells? How do ATPases u se ATP to make reactions go?

Define distribution of food products – public nutrition, Define Distributio...

Define Distribution of Food Products - Public Nutrition? We learnt earlier that we have buffer stocks of food grains in our country. These stocks do help to combat acute transi

Heat loss, Heat Loss Temperature regulation is extremely uneconomical...

Heat Loss Temperature regulation is extremely uneconomical if it depends only on variations in metabolism. Therefore, mechanisms for losing excess heat have been developed by

What is a homologue, Single chromosome of a pair is known as homologue.In H...

Single chromosome of a pair is known as homologue.In Homologous pair two identical chromosomes are there. Each one chromosome in a Homologous pair is known as Homologue.

Determine the occurrence of vitamin A, Determine the Occurrence of vitamin ...

Determine the Occurrence of vitamin A In the vegetable kingdom, vitamin A  probably occurs in the form of its provitamins which belong to the group of carotenes. Carrots, spina

Determine the occurrence of pantothenic acid, Occurrence Pantothenic acid ...

Occurrence Pantothenic acid Pantothenic acid is a ubiquitous active principle occurring in free as well as in the bound form. In the bound form, pantothenic acid is incorpor

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