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

Potential and excitation threshold for neurons, Q. How different are the co...

Q. How different are the concepts of action potential, resting potential and excitation threshold concerning neurons? Action potential is the maximum positive voltage level ach

Mycotic diseases, Mycotic diseases Mycotic (fungal) diseases of animal...

Mycotic diseases Mycotic (fungal) diseases of animals and birds are of considerable importance both from public health and economic point of view. The fungi responsible for an

Drugs for sexually transmitted infections, Drugs for Sexually Transmitted I...

Drugs for Sexually Transmitted Infections Many infections can be transmitted during sexual contact. The text and tables that follow are limited to management of sexually transm

What is patient''s plasma osmolarity after the infusion, Tina administered ...

Tina administered 1 liter of sterile distilled water IV to a patient. Predict the direction (increase, decrease, no change) you would expect Tina's infusion to have produced in the

What are the dietary goals for diabetes, Q. What are the dietary goals for ...

Q. What are the dietary goals for diabetes? Well here they are. These are to: 1. Supply optimum nutrition to maintain good health, 2. Provide calories for maintaining ide

Female reproductive disorders-retained foetal membranes, Retained foetal me...

Retained foetal membranes The foetal membranes are normally expelled within 6to 12 hr after parturition in cows and buffaloes. If the foetal membranes are not voided even upto

Antibiotic resistance, Antibiotic resistance is the resistance conferred t...

Antibiotic resistance is the resistance conferred to the host the ability to survive a given antibiotic by the plasmids containing resistance genes. If such kind of plasmid is pre

What is the form that produces gametes, In the metagenesis of Aurelia and O...

In the metagenesis of Aurelia and Obelia what is the form that produces gametes? What is the form that reproduces asexually? In the metagenesis of some coelenterates, like Obel

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