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

Types of stress caused by freezing, Types of Stress Caused by Freezing ...

Types of Stress Caused by Freezing Thus, freezing can cause the following kinds of stresses Lowering of temperature to suboptimum thus reducing the activity of mo

Summary of determinants of health status, Normal 0 false fals...

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

Zoology , canal system in porifera

canal system in porifera

Introduction to avian infectious diseases, Poultry birds are affected with ...

Poultry birds are affected with many types of ailments; broadly these are classified on the basis of etiology as non-infectious and infectious conditions. Non-infectious diseases a

Therapeutic diets - qualitative methods, Therapeutic diets - Qualitative me...

Therapeutic diets - Qualitative methods Qualitative methods: This  is where  you  give  the individual choices,  clear guidelines, menu guidance and supporting  information  su

Define functions of copper, Define Functions of Copper? Copper serves a...

Define Functions of Copper? Copper serves as a co-factor, as well as, an allosteric component of enzymes. In many enzymes copper functions as an intermediate in electrno transf

The formation of macro and micronuclei of daughter paramoeci, The formation...

The formation of macro and micronuclei of daughter paramoeci: Each exconjugant has a single micronucleus and four macronuclei. This type of exconjugant divides twice and f

Congenital aortic stenosis-types of aortic stenosis, Congenital Aortic Sten...

Congenital Aortic Stenosis :  The valve may be unicuspid, bicuspid or tricuspid. Rarely it is a dome shaped diaphragm. Uni commissural aortic stenosis produces significant sy

Food, FOOD Food consists of H O, minerals, vitamins carbohydrate, li...

FOOD Food consists of H O, minerals, vitamins carbohydrate, lipid & protein. A person needs 1600 cal. per day. This is BMR (Basal metabolic rate). Needed 2500 cal. per

What is radiographic template, What is Radiographic Template Radiograp...

What is Radiographic Template Radiographic Template : You should always use it while taking a panoramic radiograph of the patient. It is done to counter the effect of magnific

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