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

Medical therapy for tricuspid stenosis, Q. Medical therapy for tricuspid st...

Q. Medical therapy for tricuspid stenosis? Medical therapy is ineffective. With diuretics, symptoms of congestion are replaced by that of low cardiac output state. Occasional c

State about the halsted reitan battery, State about the Halsted Reitan batt...

State about the Halsted Reitan battery The Halsted Reitan battery, as the procedure came to be known over the years, also has a history. It has been described as a fixed batter

What do you understand by haemagglutinins, Q. What do you understand by Hae...

Q. What do you understand by Haemagglutinins? Haemagglutinins are the globulin type of proteins which are present in the seeds of plants like double bean, field bean, white be

Checker board (punnet''s square) method, CHECKER BOARD (PUNNET'S SQUARE) ME...

CHECKER BOARD (PUNNET'S SQUARE) METHOD 1.         If the genotypes of the parents are known, the genotypes of their offspring can be easily predicted with the help of a chart c

Where may bacteria be found, Where may bacteria be found? Expose steril...

Where may bacteria be found? Expose sterile bacteria dishes to as lots of the following conditions as you can. Label the dishes and set them away in a warm, dark place for a so

Importance of biodiversity, T hese are some important uses of biodiversity....

T hese are some important uses of biodiversity. 1.   Source of food, medicines and drugs: (a)       Wheat, rice and maize are three carbohydrate rich crops and contribute

Care of psychoemotional aspects of patient in icu, Care of Psychoemotional ...

Care of Psychoemotional Aspects ICU area is an area which is cut off from outside world. Modem ICUs are built in such a way that the sensory deprivation is reduced. Ta

What do you mean by descending aorta, Q. What do you mean by Descending Aor...

Q. What do you mean by Descending Aorta?  The descending aorta begins at the level of the fourth thoracic vertebra. It is defined through the cardiac shadow on the CXR, as it l

What is the principle of the design, In designing an experiment to find out...

In designing an experiment to find out whether light is required for photosynthesis    (a) what is the principle of the design    (b) what control would you use?

Why pregnancy and lactation are critical stages in lifecycle, Why Pregnancy...

Why Pregnancy and lactation are critical stages in lifecycle? You must be aware that the situation of women is far from optimal and it is necessary to give attention to their n

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