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

How do you define normal pulmonary vasculature, Q. How do you define Normal...

Q. How do you define Normal Pulmonary Vasculature? Pulmonary vessels are seen in the medial 2/3 of the lung. Vessels are generally not identified in the lateral third. The rad

Illustrate sequential phases of the cell cycle, Q. How does the quantity of...

Q. How does the quantity of genetic material differ within the cell during the sequential phases of the cell cycle? The first period of the first phase interphase of the cell c

Explain about the ocular haemodynamics, Explain about the Ocular Haemodynam...

Explain about the Ocular Haemodynamics. The pressure in the ocular arteries can be measured by optical ophthalmodynamometer. The intraocular pressure is raised to the level tha

Nutrition, type of nutrition in platypus and ant eater

type of nutrition in platypus and ant eater

Electron transport chain, ELECTRON TRANSPORT CHAIN All processes requir...

ELECTRON TRANSPORT CHAIN All processes require energy. In living cells, we constantly use energy for a number of biochemical reactions e.g. muscular movements, synthesis  of ne

What are the physical signs of mitral stenosis, Q. What are the Physical Si...

Q. What are the Physical Signs of mitral stenosis? A typical malar flush is described in mitral stenosis. It is difficult to appreciate in Indians. Pulse is normal or low volum

Explain the histologic techniques, Explain the histologic techniques A...

Explain the histologic techniques A clinician has to base the diagnosis only on the clinical and radiographic findings as microbiologic and histologic techniques are restricte

Explain the endosperm of angiosperms, How different are the endosperm of gy...

How different are the endosperm of gymnosperms and the endosperm of angiosperms? In gymnosperms the endosperm is haploid (n), it is known as primary endosperm. In angiosperm th

How is striped pattern of the striated muscle cells formed, How is the stri...

How is the striped pattern of the striated muscle cells formed? The functional units of the muscle fibers are the sarcomeres. Within the sarcomeres blocks of myosin and actin

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