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

Name the system that contains three neurons, Name the system that contains ...

Name the system that contains three neurons Consider a system that contains three neurons in a culture dish bathed in normal physiological saline.  All three neurons are health

What is the results of congenital pulmonary stenosis, What is the Results o...

What is the Results of Congenital Pulmonary Stenosis? Early mortality for open pulmonary valvotomy in neonates varies between 6 and 10 per cent. For infants and children, surgi

Explain the basal metabolic rate, Explain the Basal Metabolic Rate? The...

Explain the Basal Metabolic Rate? The Basal Metabolic Rate (BMR) gradually decreases after the attainment of maturity due to a decrease in muscle mass tissues and physical acti

Describe the two pieces of evidence, Describe two pieces of evidence indica...

Describe two pieces of evidence indicating that speciation does not always occur at the same rate. Some species of moths on the Hawaiian Islands appear to have evolved during t

What do you mean by borrowed materials, Q. What do you mean by Borrowed Mat...

Q. What do you mean by Borrowed Materials? For the study of as much relevant material as possible the material is obtained on loan. Borrowed specimens benefit the' lending inst

Assessment of peripheral vascular perfusion (beside test), Assessment of Pe...

Assessment of Peripheral Vascular Perfusion (Beside Test) Burger's Postural Test Perform in daylight.  Place patient supine with both legs elevated and knees

What is the chemical content of those organelles, Q. On which organelle of ...

Q. On which organelle of the cell structure does intracellular digestion depend? What is the chemical content of those organelles? Intracellular digestion take place by the act

Explain severe acute respiratory syndrome, Severe Acute Respiratory Syndrom...

Severe Acute Respiratory Syndrome (SARS) After travelers' diarrhea, respiratory infection is the most common infectious disease affecting travelers. In the winter of 2003 a ne

Define about the environmental deficiency of iodine, Define about the Envir...

Define about the Environmental deficiency of iodine? The ultimate causative Factor is deficient intake of iodine. Iodine occurs in soil and sea as iodide, the ions of which arc

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