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.
What is the primary structure of a protein? What is the significance of the primary structure? The primary protein structure is the linear sequence of amino acids that form the
Define Factors that Affecting the BMR? Basal metabolic rate, we know, is the largest component of the daily energy demand representing 45 to 70 percent of daily total energy ex
Describe in detail about the chlorophyll molecule Each chlorophyll molecule contains magnesium ion, there could be no green plants without magnesium. As magnesium is present in
What is photoperiodism? Photoperiodism is the biological response shown by some living beings to their daily time of light exposure (photoperiod).
Define classification of carbohydrates - Polysaccharides? This classification is based on the number of monosaccharide units they contain, Polysaccharides are those polymers of
Q Which is the kind of nitrogen waste birds produce? Why does this feature, besides being an adaptation to the terrestrial environment, also mean an adaptation to flight? Birds
What are the tupes of Aortic Aneurysm Surgery? Types of Surgery : Technique of surgery and the approach depends on the site of thoracic or thoraco abdominal aortic aneuiysm.
(a) What are the two main pollutants that contribute to acid rain? (b) Where do these pollutants come from? (c) What direct or indirect effect is 'acid rain
The transport system in earthworm The scientific name of earthworm is megascolex. It consists of hearts, blood vessel and blood. There are 8 pairs of hearts in the earthw
HAIR Presence of hair is main feature of mammals, absent in whale fish. Soft hair in embryo of animals are lanugo. Study of hair is tricology . Part of hair which
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