Explain cephalization in nematodes and platyhelminthes, Biology

Assignment Help:

How is the nervous system characterized in beings of the phylum Annelida? How can one compare cephalization in annelids to cephalization in nematodes and platyhelminthes?

Annelids have a nervous system made of two ventral chords and one relatively big nervous cell concentration in its anterior portion resembling a primitive brain.

Nematodes have an anterior neural ring connected to two neural chords, a ventral and a dorsal one, while in planarias (platyhelminthes) there are only two small anterior "cerebral" ganglia from which neural chords split. Cephalization in annelids thus is more outstanding than in nematodes or in flatworms.

 


Related Discussions:- Explain cephalization in nematodes and platyhelminthes

What is active transport--secretion, What is Active Transport--Secretion ...

What is Active Transport--Secretion This method is now a well accepted process of aqueous formation. The rate of aqueous humour formation depends on the rate of active solute

What is extracellular digestion, What is extracellular digestion? Extra...

What is extracellular digestion? Extracellular digestion is that in which food breaking into utile molecules that can be internalized by the cell is completed in the extracellu

Cyanide - enzyme-activity control, Cyanide - Enzyme-activity Control P...

Cyanide - Enzyme-activity Control Plants generate cyanide from cyanogenic glucides and histidines. Ethylene biosynthesis is also accompanied by cyanide production. Nitrate red

Functions of skin, FUNCTIONS OF SKIN - Skin performs various diverse fu...

FUNCTIONS OF SKIN - Skin performs various diverse functions, that is why it is called "jack of all trades". 1 .      Protection - The skin protects the internal soft or

Activitiesthat cause fish kills, Explain how human activities can cause an ...

Explain how human activities can cause an imbalance in biogeochemical cycling and lead to problems such as cultural eutrophication and fish kills

Apical ectodermal ridge or aer, Apical Ectodermal Ridge (AER) We have ...

Apical Ectodermal Ridge (AER) We have described earlier that the AER persists at the tip until the last phalangeal cartilage begins differentiation. The following experiments

Explain tuberculosis, Tuberculosis Tuberculosis is a chronic infectious...

Tuberculosis Tuberculosis is a chronic infectious disease which is caused by a bacterium - Mycobacterium tuberculosis.  It affects the lungs most commonly but call gel localize

What do you mean by syphilis, Q. What do you mean by syphilis? The Syph...

Q. What do you mean by syphilis? The Syphilis, as well known as lues, is a disease caused by the bacteria Treponema pallidum. Before the invention of penicillin, syphilis was a

What is signifying by concentration gradient, Q What is signifying by conce...

Q What is signifying by concentration gradient? Is it correct or not to refer to "concentration gradient of water"? Concentration gradient is the variation of concentration of

Complications during rheumatic heart disease, Q. Complications during rheum...

Q. Complications during rheumatic heart disease? Inflammation of Inning of heart (pericarditis), anaemia, heart ,enlargement, valve deformities (mitral and tricuspid valves),

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd