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 allele frequency, What is allele frequency? The Allele frequenc...

What is allele frequency? The Allele frequency is the percentage of appearances of an allele in the genotypes of a given population (compared to the other alleles of the studie

Define results of miscellaneous conditions, Results :  In the present day,...

Results :  In the present day, surgical mortality with or without CABG is repture to be 5-7 per cent. The late survival is 85 per cent, 75 per cent and 65 per cent at 1, 3 and 5

Which is most likely be fatal to marin fish populations, If we were to comp...

If we were to completely eliminate one group of marine organisms from ocean, which would most likely be fatal to Marin fish populations? Elimination of: a) Starfishes b) Dia

Titanium and its alloys - alloplastic implant materials, Titanium and Its A...

Titanium and Its Alloys - Alloplastic implant materials These have been used primarily for their corrosion resistance and biocompatibility. Titanium exists in nature as a pure

Prevention of overloading the sterilizer, Prevention of overloading the ste...

Prevention of overloading the sterilizer Most sterilizers have a system to notify the operator of mechanical malfunction, but sterilizers cannot notify the operator whether the

Define about the sucrose and trehalose, Define about the Sucrose and Trehal...

Define about the Sucrose and Trehalose? Sucrose, also called saccharose, is ordinary table sugar refined from sugar cane or sugar beets. Trehalose has two a-D-glucose molecu

Explain the endocrine glands involved in the menstrual cycle, What are the ...

What are the endocrine glands involved in the menstrual cycle? What are the hormones in action? The endocrine glands that secrete hormones included in the menstrual cycle are t

Chlorophyll, Chlorophyll is the pigment in the green plants which absorbs ...

Chlorophyll is the pigment in the green plants which absorbs solar energy.   chlorophyll a -  It is a green photosynthetic pigment common to all the photosynthetic organisms.

What are exocrine respective hormones and enzymes, What are the pancreatic ...

What are the pancreatic tissues involved respectively in the exocrine and endocrine secretions? What are their respective hormones and enzymes? The exocrine secretion of the pa

Tissue culture, Note on production of haploid by tissue culture.

Note on production of haploid by tissue culture.

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