How is the nervous system characterized, Biology

Assignment Help:

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

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 dorsal one and a ventral, 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 flatworms or in nematodes.


Related Discussions:- How is the nervous system characterized

Development of binomial nomenclature, Q. Concept of Development of binomial...

Q. Concept of Development of binomial nomenclature? Name is a conventional tool to act as means of reference. For example, when we say chimpanzee, sparrow, paddy, virus, we mea

Define proteins, Define Proteins, Carbohydrates required for anorexia nervo...

Define Proteins, Carbohydrates required for anorexia nervosa? A. Proteins To ensure adequacy, minimum protein intake should equal the recommended dietary intake for age and

What are the main classes into which the phylum is divided, What are the ma...

What are the main classes into which the phylum is divided? What are some examples of each and in which form (polyp or medusae) are they found? Coelenterates are separated into

Explain antioxidants, Antioxidants  Antioxidants are the substances tha...

Antioxidants  Antioxidants are the substances that can delay onset, or  slow the rate of oxidation of autoxidizable materials. By virtue of this property,  they provide protect

Catecholamines, Catecholamines increase activation of Ca 2+ via beta-adren...

Catecholamines increase activation of Ca 2+ via beta-adrenergic receptors and the adenyl cyclase system. Dopamine has both alpha and beta and dopaminergic effects.  Its beta ef

Adaptations, what are some adaptations of flatworms

what are some adaptations of flatworms

Atelectasis and pneumonia - complications of cardiac surgery, Atelectasis a...

Atelectasis and Pneumonia Signs and symptoms are LV failure, hypovolemia, hypervolemia or renal vasoconstriction. Decreased breath sounds, poor ABG and poor cough reflex

Suspensor - pollen biology, Suspensor - Pollen Biology The structure a...

Suspensor - Pollen Biology The structure and function of suspensor have not been given adequate attention. During the last decade, however, investigations have produced notewo

Describe components of a complete diagnosis, Describe Components of a Compl...

Describe Components of a Complete Diagnosis of Congenital Heart Disease ? A complete diagnosis of congenital heart disease requires accurate and thorough description of the he

Why plants need to do exchange gases with the environment, Why plants need ...

Why plants need to do exchange gases with the environment? The Plants need to do gas exchange because they create aerobic cellular respiration (like animals) and they need to r

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