Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Origin and Evolution of Metazoa
Most of the early metazoans were soft bodied and so their fossils are rare. The extremely fragmented fossil record does not shed any specific light on their origin. Therefore, 'most of the explanations on their origin are based on their embryology and -comparative morphology. A series of theories have been put forward to explain the origin of multicellular metazoans from unicellular organisms. Of these, three principal theories could be considered.
1) Syncytial Theory: That the ancestral metazoans have arisen from a multinucleate. ciliate by compartmentalization or cellularization.
2) Colonial Theory: That the ancestral metazoans have arisen from colonial flagellates by cellular specialisation and interdependency.
3) Polyphyletic Theory: That the metazoans have arisen from more than one group of organisms.
Coarse fish reach or lowland course zone This zone corresponds to the lower course of the river. Here the river is deep and slow moving. Its sluggish flow results in the depos
How different are fecundation in osteichthyes and in chondrichthyes? In chondrichthyes fecundation is internal by means of copulation. In osteichthyes fecundation generally is
What are Fitness Tests? Testing is an important evaluation tool for the sports performer as it gives them an insight into their current physical condition and the effectiveness
????? # 100 ??????????? #Minimum ?????? ?????
what is the excitation threshold of a neuron?how does this threshold relate to the all or nothing rule of neural transmission
Preparation of Patient for Fasting Blood Sugar Analysis 1. Blood for fasting blood sugar (plasma glucose) analysis should be drawn after the individual has fasted overnight (8-
How many grams of sodium dodecyl sulfate (mw = 288.37) would you dissolve in 80mLs of water to make a 20% solution of SDS?
What is Mega sporogenesis
Methods Useful in Self-Incompatibility More specific methods useful in overcoming self-incompatibility are mentioned below 1. Bud Pollination : In Petunia axillaris early
Q. Can you explain Aneurysm of Aorta? CXR findings are an enlargement of the involved portion of the aorta. A focal dilatation may simulate a mass or adenopathy. A more general
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd