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

Nervous system, Nervou s System It is controling system of body. ...

Nervou s System It is controling system of body. Ectodermal in origin. This system is made up of nervous tissue. Nervous tissue is made up of neuron & neuroglial

Splenic abscess, Splenic infarction is a common complication of left-sided ...

Splenic infarction is a common complication of left-sided IE (40 per cent of cases). Only 5 per cent of patients with splenic infarction will develop splenic abscess. This infectio

The trp operon, The trp (tryptophan) operon which is shown in the figure wi...

The trp (tryptophan) operon which is shown in the figure will have  five  structural  genes  encoding enzymes  for tryptophan  biosynthesis  with an upstream  Ptrp  (trp promoter)

Comparison of cabg and angioplasty, Comparison of CABG and Angioplasty : ...

Comparison of CABG and Angioplasty :  Results of six major randomized clinical trials of multi vessel angioplasty Vs CABG are now available. The main conclusions are: Patient

Nutrition, Nutrition, Feeding, Digestion All organisms require a fairl...

Nutrition, Feeding, Digestion All organisms require a fairly steady supply of nutrient materials from the environment to obtain energy in order to stay alive. The animals are

Diverse proteins made by the same total number of amino acid, Q. Are there ...

Q. Are there diverse proteins made by the same total number of amino acids? Diverse proteins with the same total number of amino acids may exist. In such cases the discriminati

Agro industrial-magnesium, Magnesium Magnesium is closely related to c...

Magnesium Magnesium is closely related to calcium and phosphorus in its dispersion and functions in the body. Most of the body’s magnesium is found in bones and muscles. Grass

How can bacteria produce human insulin, How can bacteria produce human insu...

How can bacteria produce human insulin on an industrial scale? What are the other forms of insulin made available by the pharmaceutical industry? Bacteria do not naturally synt

Autumn (fall) overturn, Autumn (fall) overturn In autumn or early wint...

Autumn (fall) overturn In autumn or early winter the air temperature falls, resulting in the cooling of the surface waters. When the surface water cools to 4°C it becomes dens

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