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!
Syncytial Theory - Metazoa
This theory suggests that the ancestral metazoan was at ,first Syncytial in structure but later became cellularised by formation of cell membranes around individual nuclei this producing a typical multicellular body. Hadzi (1953) and Hanson (1977) have been the chief proponents of this theory. As many ciliates tend to have a bilateral symmetry, the advocates of this theory maintain that the ancestral metazoan was bilaterally symmetrical similar to the present day acoelous flatworms. The theory receives support from the fact that acoelous flatworms are
Figure: Possible routes for evolution of animals
There are several objections to this theory. It ignores the embryology of flatworms in which nothing similar to cellularization occurs, nor does it explain the presence of flagellated sperms in metazoans. Perhaps the most important objection to this theory is that it assumes that .acoelous flatworms are the most primitive metazoans and therefore, presumes bilateral symmetry to be more primitive than radial symmetry and thus radial coelenterates must have been derived from bilateral flatworms. But then it is accepted that radial symmetry is more primitive than bilateral symmetry and radial coelentrates could not have evolved from flatworms.
Explain the Kingdom Fungi organisms? Kingdom Fungi consists of mostly eukaryotic, multicellular, non-photosynthetic organisms that derive their nutrients by absorption. Fungi
Biological Valves : Biological valves are available for all positions. For mitral position they are usually mounted on a stent (stent mounted) whereas for aortic position they ma
It is a complex of antibody bound to antigen, which contains complement components.
Inhibitor Proteins - Enzyme-activity Control One kind of inhibitor protein found in higher plants is an endopeptidase which degrades nitrate reductase thus causing irreversibl
Explain Metabolic changes during infection With the rise in body temperature above normal (98.4 0 F or 37°C) due to infection several metabolic changes occur in the body
what is the mode of nutrition in pisces
Many common methods are employed for the removal of impurities from water. Some of them are: Sedimentation Filtration Reverse osmosis Electro dialysis Aeration
The bonding geometry of C,O,N is determined by- Select one: a. The number of electrons in their outer energy level b. SP3 hybridization of orbitals in the valence shell
Q. Why are transgenics considered a threat to the environmental safety? The Transgenics can be dangerous to the whole biosphere since the transfer of genes between species may
Q. How Cleaning agents works? Food particles and other debris provide good nutrients for the nlicroorganisms to grow. In fact, the food particles protect microorganisms d
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