Patters of cleavage, Biology

Patters of Cleavage

In most of the animal groups with spherical or almost spherical egg and little or moderate amount of yolk (micro-or mesolecithal eggs), the first and second divisions result in four blastomeres of almost equal size. Because of greater concentration of yolk platelets in the vegetal hemisphere, the third cleavage divides the 4 blastomeres in latitudinal plane giving rise to 8 cells arranged in two tiers of 4 blastomeres each including one tier of 4 small blastomeres (micromeres) in the animal hemisphere and the second tier of 4 large blastomeres (macromeres) in the vegetal hemisphere. The arrangement of blastomeres in these two tiers is very distinct and on this basis, the cleavage may be of:

  • Radial Type
  • Spiral Type
Posted Date: 1/25/2013 1:01:51 AM | Location : United States







Related Discussions:- Patters of cleavage, Assignment Help, Ask Question on Patters of cleavage, Get Answer, Expert's Help, Patters of cleavage Discussions

Write discussion on Patters of cleavage
Your posts are moderated
Related Questions
Q. What is a population? In the Biology a population is a set of individuals of the same species living in a given place and in a given time.

what are the disadvantages of protozoa

Your client has the flu and reports 5-6 loose stools a day. He has experienced an isotonic fluid volume loss. Explain what an isotonic fluid loss means.

Unsaturated fatty acids require some additional processing before they can be degraded completely by β-oxidation.  The Unsaturated fatty acyl CoAs with double bonds at odd-numbered

function of epithelial tissue

Design a controlled experiment to test the hypothesis that acid precipitate inhibits the growth of elodea, a common freshwater plant.

Why do protease-supplying cells of the stomach and of the pancreas make only precursors of the active proteolytic enzymes? The stomach and the pancreas make zymogens of the pro

(1) From the above gateway reaction (entry clone and destination vector); (i) which plasmid will be selected for when transformed into E.coli (A or B) and why? (ii) which an

Q. Show the Use of Incineration for sterilization? This is an excellent method for rapidly destroying materials such as soiled dressings, animal carcasses, bedding and patholog

Q. Explain Therapy of Specific Lipid Disorders? a) Very high LDL levels usually result from inherited disorders of lipoprotein metabolism and carry a high risk of premature at