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

Explain what is prosthetic valve endocarditis, Explain what is Prosthetic V...

Explain what is Prosthetic Valve Endocarditis (PVE) ? Prosthetic valve endocarditis (PVE) is called EARLY when symptoms begin within 60 days of surgery and LATE when the onset

Describe the organization of the vascular plant body, Describe the Organiza...

Describe the Organization of the Vascular Plant Body? A typical plant body consists of two distinct systems: a root system and a shoot system. The root system is usually below

Explain particle movement , Explain Particle Movement ? Particle Mov...

Explain Particle Movement ? Particle Movement :  Particles are moved down a concentration gradient by the process of diffusion. Osmosis is simply the diffusion of water acr

Agro industrial-cobalt, Cobalt Cobalt functions as a component of vitamin ...

Cobalt Cobalt functions as a component of vitamin B12  (cobalamin). Ruminants are not dependent on a dietary source of vitamin B12  because ruminal microorganisms can synthesize B

Calculate the efficiency of photosynthesis, Figure  shows the flow of energ...

Figure  shows the flow of energy through the trees in a forest ecosystem.The numbers represent inputs and outputs of energy in kilojoules per m 2   per year. (a)  (i) On Figure,

Objectives of diabetes counselling, Objectives of Diabetes Counselling    ...

Objectives of Diabetes Counselling      1.  Facilitating decision to start treatment and change life style 2.  Providing psychological, social and emotional support for a.

Give an introduction to intensive care, Give an introduction to intensive c...

Give an introduction to intensive care ? Intensive Care Medicine has its origins from the polio epidemic of 1952 in Copenhagen. Patients who suffered respiratory paralysis were

Captive breeding - measures for species conservation, Captive Breeding - Me...

Captive Breeding - Measures for Species Conservation Species which are reduced to dangerous levels need more intensive management, and one strategy is their captive breeding.

Care of psychoemotional aspects of patient in icu, Care of Psychoemotional ...

Care of Psychoemotional Aspects ICU area is an area which is cut off from outside world. Modem ICUs are built in such a way that the sensory deprivation is reduced. Ta

Mass dispersal - population dispersal, Mass Dispersal - Population Dispersa...

Mass Dispersal - Population Dispersal A population is inherently dynamic in nature since individuals are always leaving or entering the populations. But such changes normally

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