Polyphyletic theory - metazoa, Biology

Polyphyletic Theory - Metazoa

This theory was suggested by Greenheig (1959) and some other workers. According to this theory, sponges, coelenterates, ctenophores and flatworms have each evolved independently from protozoans. Sponges and coelenterates have probably arisen through colonial flagellates, while ctenophores and flatworms through ciliates or even mesozoans.

It is apparent that this theory is a compromise between the Syncytial and colonial theory.

Posted Date: 1/15/2013 2:56:38 AM | Location : United States







Related Discussions:- Polyphyletic theory - metazoa, Assignment Help, Ask Question on Polyphyletic theory - metazoa, Get Answer, Expert's Help, Polyphyletic theory - metazoa Discussions

Write discussion on Polyphyletic theory - metazoa
Your posts are moderated
Related Questions
Briefly explain about the Flexed-arm Hang Test? Persons who cannot do one pull-up may do the flexed-arm hang. Using the same hand position as in pull-ups, subject takes flexed-

Oxidation Some enzymes which have the sulfhydryl (-SH)  group in  the catalytic site are very sensitive to oxidation. Due  to oxidation of  the  -SH  group  by  aerial  oxygen

What is Single Ventricle Physiology ? In complete correction of a congenital cardiac condition, it is ideal to have two ventricle correction (Pulmonary and systemic ventricles

Define the Rehabilitation Phase of spinal trauma disease? Once the patient s condition stabilizes, individualized diets need to be recommended, based on the energy and nutrient

Q Which is the biological molecule that holds the genetic information that is transmitted hereditarily and controls the cellular functioning? The hereditary molecule that contr

In developing countries because of poor compliance, poverty, ignorance, primary and secondary prevention strategies are difficult to implement properly. Also in western countries (

Anti Platelet Drugs In the early years of CABG, patients used to be put on aspirin and persantin (Dipyridamole). Persantin is not routinely prescribed now. Aspirin dose can b

Molluscus - Hormones in Growth and Reproduction We know quite well about the endocrine mechanism of growth and reproduction in the freshwater snail Lymnaea stagnalis. This is

What are some of the presumed target substrates for cyclin-dependent kinases?

Floral Apex Each plant must pass through a minimal 'ripeness to flower' stage. That is, even to perceive and respond to a specific photoperiodic regime, a plant must be ready