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 the function of the skin in humans, Q What is the function of the s...

Q What is the function of the skin in humans? The skin is the external covering of the body. In humans its major functions are protection and perception of information from the

What is selective waste collection, Q. What is selective waste collection? ...

Q. What is selective waste collection? The Recyclable waste is waste that can be reprocessed and used again. The waste recycling depends on the separation of the recyclable res

Effect of respiratory frequency, Q. How does the pulmonary ventilation affe...

Q. How does the pulmonary ventilation affect the carbon dioxide concentration in blood? What happens to the carbon dioxide concentration and to the blood pH when the respiratory fr

Fat soluble vitamin needs of school children and adolescents, Determine Fat...

Determine Fat Soluble Vitamin Needs of school children and adolescents? ICMR (1990) does not give recommendations for vitamin D, E and K. Vitamin D is very important for skelet

Limiting factors of green plants, What are likely to be the limiting factor...

What are likely to be the limiting factors in a population of (a) green plants, (b) birds?  (a) In green plants the limiting factors are likely to be light, water, minerals, te

What is bile salts, What is Bile salts Bile salts have a considerable...

What is Bile salts Bile salts have a considerable ability to lower surface tension. By  this property, they prevent  the coming together of the small fat droplets in  the  in

Change of health status over time, Change of Health Status Over Time Hea...

Change of Health Status Over Time Health of a nation can be gauged from the available information on death.Disaggregated data by causes of death is more reflective of the status

How delayed complementary feeding cause pem, How Delayed Complementary Feed...

How Delayed Complementary Feeding Cause PEM? The mothers from poorer socioeconomic groups where PEM is more prevalent, delayed introduction of complementary foods (foods in add

Blood pressure, BLOO D PRESSURE Is the result of the sum of  ...

BLOO D PRESSURE Is the result of the sum of                 (i) Osmotic colloidal pressure of blood                 (ii) Elastic recoil of blood vessel's wall.

Formation of lactate and its consumption, Formation of  lactate and  its ...

Formation of  lactate and  its consumption Formation of  lactate and  its consumption : If anaerobic conctitions prevail, the reoxidation  of NADH  through the respiratory cha

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