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

What is primary motor cortex, Q. What is Primary Motor Cortex? Located ...

Q. What is Primary Motor Cortex? Located in precentral gyrus of frontal lobe (anterior to central sulcus, which separates frontal and parietal lobes.  Neurons called pyramidal

What is folic acid, What is folic acid? Why is the anemia caused by deficie...

What is folic acid? Why is the anemia caused by deficiency of folic acid known as megaloblastic anemia? The folic acid (when ionized it is known as folate) is a coenzyme that

What are the factors to an actual shift in the supply curve, What are the f...

What are the factors to an actual shift in the supply curve? Factors which cause an actual shift in the supply curve are described in below: When prices rise or fall this wo

Rabbit, reproductive system of rabbit

reproductive system of rabbit

Define interaction of niacin with other nutrients, Define Interaction of ...

Define Interaction of niacin with other Nutrients? You may recall reading earlier that trypotophan present in dietary proteins is converted to niacin. There is an interdepend

What are the grasslands of north and south america, What are the grasslands...

What are the grasslands of North America and of South America respectively called? The steppe the grasslands of North America are called as prairies . The grasslands of South

How implants increases the magnitude significantly, How implants increases ...

How implants increases the magnitude significantly The patient should be medically fit to undergo the surgery. Placement of one or two implants is equivalent to relatively mino

Types of blastula, TYPES OF BLASTULA - Blastulas are of following type ...

TYPES OF BLASTULA - Blastulas are of following type -                    1 .       STEREOBLASTULA - The blastocoel is very small. It's blastomere are less in num

What compound composes most of the cell membrane, What compound composes mo...

What compound composes most of the cell membrane? How is this compound suited to the function of the membrane? Phospholipid composes most of the cell membrane. The hydrophob

Digestive system of mammals, DIGESTIVE  SYSTEM OF MAMMALS The tube f...

DIGESTIVE  SYSTEM OF MAMMALS The tube from mouth up to anus is called alimentary canal. Alimentary canal of man is about 9 meter and rabbit is about 6 meter. Digestive

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