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

In unilocular ovary with a single ovule the placentation, In unilocular ova...

In unilocular ovary with a single ovule the placentation is : 1. Marginal 2. Basal 3. Free Central 4. Axile Basal

Marine biology, What are the four characteristics that all chordates have ...

What are the four characteristics that all chordates have at some stage of their lifecycle ?

What is dinoflagellates, What is Dinoflagellates ? Dinoflagellata or...

What is Dinoflagellates ? Dinoflagellata or dinoflagellates , are characteristically unicellular photosynthetic organisms that usually have two flagellae. One flagellum typi

For the biological diversity is mitosis or meiosis, For the biological dive...

For the biological diversity is mitosis or meiosis the more important process? Meiosis is the cell division process that permits the formation of gametes to sexual reproduction

The best describes the acid properties of guanine, Which statement best des...

Which statement best describes the acid/base properties of guanine? -at pH, guanine will be negatively charge -at pH, guanine will be neutral -it will be an effective buff

Assessment of tubercular meningitis, Assessment   For assessment of cli...

Assessment   For assessment of clinical manifestation of the disease you need to understand three stages of clinical course of the disease which are as follows:  Prodromal

Human respiratory system - thoracic cavity, THORACI C CAVITY - Thor...

THORACI C CAVITY - Thoracic cavity is air tight. On dorsal side vertebral column present. On ventral side sternum present. On lateral side 12 pairs ribs present. On p

Energy and protein deficiencies, Energy and protein deficiencies Defic...

Energy and protein deficiencies Deficiencies of protein and energy are the most common nutrient deficiencies, which adversely affect production and performance of farm animals

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