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

Original density in CFU/ML, a nutrient agar plate labelled 10^(-5)ml had 15...

a nutrient agar plate labelled 10^(-5)ml had 154 colonies after incubated. what is the cell density in the original sample

Explain the effect of deficiency of thiamin, Explain the Effect of Deficien...

Explain the Effect of Deficiency of Thiamin? Thiamin deficiency causes the disease beriberi in human beings, which has been classically considered to exist in dry (paralytic) a

Chemical equation of the aerobic cellular respiration, Q. What is the chemi...

Q. What is the chemical equation of the aerobic cellular respiration? The chemical equation of the aerobic cellular respiration is given below: C 6 H 12 O 6 + 6 O 2 + 36 A

How different are fecundation in chondrichthyes, Q. How different are fecun...

Q. How different are fecundation in chondrichthyes and in osteichthyes? In chondrichthyes fecundation is internal by resources of copulation. In osteichthyes fecundation genera

Procedure for preparation of selective & differential medium, Procedure for...

Procedure for Preparation of Selective and Differential Medium Now prepare the MacConkey agar medium following the steps given herewith: 1. Weigh and dissolve all ingredient

Examples of tissues and organs where mitosis is frequent, Q What are some e...

Q What are some examples of tissues and organs where mitosis is more frequent, less frequent or practically absent? Generally in vertebrates mitosis is more frequent in tissues

How many heart chambers does the amphibian heart have, Q. How many heart ch...

Q. How many heart chambers does the amphibian heart have? The amphibian heart has three heart chambers such as one ventricle and two atria.

Define water output (losses of body water) - renal loss, Define Water Outpu...

Define Water Output (Losses of body water) - Renal loss? Water is lost from the body by the four routes, namely kidneys (renal system), skin, lungs and intestine. Let us discus

Run off-water cycle, Run off Some of the rainfall is soaked into the so...

Run off Some of the rainfall is soaked into the soil and excess water flows over the land surface along the natural slope of the area. Run off is the main source of water for l

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