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

Describe the working of golgi bodies, Define in brief about the Golgi bodie...

Define in brief about the Golgi bodies In a cell is achieved in a remarkable fashion by the Golgi bodies. The latter receive the newly synthesised proteins from the rough endop

Axon, Axon: Axon is a projection from the cell body. Each neuron ...

Axon: Axon is a projection from the cell body. Each neuron has only one axon. Unlike dendrites, axons are very long and are usually unbranched structures. The axon

Give source organism of the dna polymerase used in pcr, a) Mention the numb...

a) Mention the number of primers needed in each cycle of polymerase chain Reaction (PCR) . Write the role of primers and DNA polymerase in PCR. b) Give the characteristic fea

Explain gastro-intestinal system, Explain G.I. (Gastro-Intestinal) system? ...

Explain G.I. (Gastro-Intestinal) system? A. Skeletal muscles directly control the movement of substances at the entrance of the G.I. system. B. Smooth muscles control the mo

Define lamivudine, Lamivudine This oral antiretroviral nucleoside analo...

Lamivudine This oral antiretroviral nucleoside analog used to treat HIV is also FDA-approved for treatment of chronic HBV infection. A trial in Asian patients with chronic HBV

Open pulmonary valvotonzy, Open Pulmonary Valvotonzy, I nfundibular Rese...

Open Pulmonary Valvotonzy, I nfundibular Resection and Trans Annular Patch :  The pulmonary annulus may be narrow based on pre-operative investigations and on measurement

Cardio pulmonary resuscitation, CARDIO PULMONARY RESUSCITATION: Cessat...

CARDIO PULMONARY RESUSCITATION: Cessation of cardiac activity is determined by  inability to palpate a central pulse,  unresponsiveness and Gnea. CPR consists of  measures for

Determine the parts of sphygmomanometer, Determine the Parts of sphygmomano...

Determine the Parts of sphygmomanometer Parts of sphygmomanometer consists of: - an inflatable cuff (wrapped around the arm when checking B.P) at vertical height as the hear

Importance of nutritional needs for management of emergency, Define Importa...

Define Importance of nutritional requirements for management of emergencies? Knowledge of nutritional requirements for management of emergencies is therefore, important due to

Medical records, Medical Records This includes: health history o...

Medical Records This includes: health history of patient/client  a report of the findings on examination  signs and symptoms  observation records  progress

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