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.
Palynofossil s (Microfossils) - Fossils of planktons, diatoms, unicellular algae (diatoms) and shelled protozoans. (Heliozoans, Radiolarian and Foraminifera). Its finding in s
Blood from the fetus circulates through the placenta. a) What substances pass (i) from the maternal to the fetal blood, (ii) from the fetal to the maternal blood?
Although fructose does not have an aldehyde group it reacts first of all bonds of fructose was breaked by fehling solution then fructose coverted to aldehydic group then that
Define the V2 receptor antagonist A new drug named ANTI-V2R has been developed that is a V2 receptor antagonist. When ANTI-V2R binds to a V2 receptor, there is no binding of v
Explain the effect on Minerals of the Human milk? There appears to be no relationship between dietary intake and concentrations in milk for copper, iron or zinc. Iron supplemen
What is the central principle of molecular biology?
Linkage of Health With Development Health, in its comprehensive or holistic sense, refers to the state of completephysical, mental, social and spiritual well being of a person.
TRANQUILLIZER S - These are the drugs that reduce tension and anxiety, bring calmness without inducing sleep. (i) Phenothiazines - These are anti psychotic drugs.
Pigs Mycoplasma infection causes arthritis in limb joints in pigs, while infection with M. hyopneumoniae gave rise to symptoms of coughing and chronic pneumonia and the disease
Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
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