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

Subphylum crustacea, Subphylum Crustacea Crustacea are mainly aquatic...

Subphylum Crustacea Crustacea are mainly aquatic arthropods with gills for respiration. Cephalothorax has usually a carapace; appendages biramous but modified for several fun

Characteristics of river systems, Characteristics of River Systems Th...

Characteristics of River Systems The basic function of the rivers is to convey surplus rain water from land to sea. Annually the rivers carry fresh water, equivalent to 25 cm

Bioluminescence, #question.which annelids shws bioluminescence .

#question.which annelids shws bioluminescence .

What are melanocytes, What are melanocytes? Melanocytes are epithelial ...

What are melanocytes? Melanocytes are epithelial cells of the skin particular in secretion of melanin. Melanin is a pigment that besides coloring the skin, the iris of the eye

Explain ventricular aneurysm in miscellaneous conditions, Indications for S...

Indications for Surgery :  95 per cent of ventricular aneurysms occur after transmural myocardial infarction. Trauma, Chaga's disease, sarcoidosis and congenital causes are the ot

Mixed mitral stenosis and regurgitation, Mixed Mitral Stenosis and Regurgit...

Mixed Mitral Stenosis and Regurgitation The most common cause for a combined lesion is rheumatic, Very rarely; it could be of congenital origin. Regurgitation in a stenotic val

Can you explain puffeelfish poisoning, Q. Can you explain Puffeelfish poiso...

Q. Can you explain Puffeelfish poisoning? Tetrodotoxin (TTX) causes pufferfish (tetrodon) poisoning, also known as blowfish poisoning or fugu. How does a pufferfish look l

Side efleects of antipsychotic drugs, Side Efleects of Antipsychotic Drugs:...

Side Efleects of Antipsychotic Drugs: The most common side effects are symptoms of central nervous system i.e. Extrapyramidal  Symptoms (EPS)  including such as:  Parkinso

What is emulsion, Emulsions  You may have eaten Mayonnaise. Some  of yo...

Emulsions  You may have eaten Mayonnaise. Some  of you may also know how it is made. Mayonnaise is a liquid in liquid  dispersion, in fact a true  emulsion.  A true emulsion re

Blastomycosis, Blastomycosis Blastomyces dermatidis is a dimorphic fung...

Blastomycosis Blastomyces dermatidis is a dimorphic fungus existing as a mold in the soil (saprophytic stage) and as a yeast in tissues (parasitic stage). It causes systemic fu

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