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

Define capsule staining (anthony staining method), Define Capsule Staining ...

Define Capsule Staining (Anthony Staining Method)? A rigid, well-organized gelatinous layer called capsule is present outside the cell wall of many bacteria e.g. Streptococus p

What is the window phase of an infection, What is the window phase of an in...

What is the window phase of an infection? How is this concept important for the test of HIV infection in blood banks? The primary immune response of the body facing any infecti

What is atopic dermatitis, Atopic dermatitis is an inflammatory skin diseas...

Atopic dermatitis is an inflammatory skin disease. This disease is observed frequently in young children. There will be skin eruptions.

What is panspermia, What is panspermia? The Panspermia is a hypothesis ...

What is panspermia? The Panspermia is a hypothesis that describes life on earth as not originated from the planet. The thought is that the first living beings that colonized th

What is a closed circulatory system, Q. Define a closed circulatory system?...

Q. Define a closed circulatory system? A closed circulatory system is one in which blood circulates only inside blood vessels for this reason the blood pressure is higher in so

Calculate the probability that both are carriers for tsd, The male had a fe...

The male had a female first cousin (on his father side) who died from TSD and the female had a maternal uncle with TSD. Assume this trait is very rare. 1. Calculate the probabil

Calculating the amounts of dissimilar nucleotides, Erwin Chargaff conducted...

Erwin Chargaff conducted a series of experiments in which he was calculating the amounts of dissimilar nucleotides that were present in dissimilar tissues and organisms. These stud

Define absorption, Define Absorption, Storage and Elimination of cyanocobal...

Define Absorption, Storage and Elimination of cyanocobalamin? Vitamin B 12 in food is bound to proteins and is only released by the action of a high 'Concentration of hydroch

Evolutionary novelty presented by annelids, Q. What is the major evolutiona...

Q. What is the major evolutionary novelty presented by annelids? The main evolutionary novelty presented by the beings of the phylum Annelida is the coelom, the internal body c

Planning the nursing care - wilms tumour, Planning the Nursing Care   ...

Planning the Nursing Care     Provide preoperative and post operative nursing care to child    Assist in therapeutic management of child.    Provide comfort.  S

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