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

Partial pericardiectomy-pericardial effusion, Partial Pericardiectomy :  ...

Partial Pericardiectomy :  The approach can be either by a left anterolateral thoracotomy or median sternotomy. For pyogenic pericarditis with adhesions and loculations a par

Dna, Double helical structure of dna

Double helical structure of dna

Show very low level of lactase activity, Q. Show Very low level of lactase ...

Q. Show Very low level of lactase activity? Very low level of lactase activity: at very low level of lactase activity all milk products must be eliminated, substitutes of milk

Explain the interaction of vitamin a with zinc, Explain the interaction of ...

Explain the interaction of vitamin a with Zinc? Its deficiency interferes with vitamin A metabolism. It leads to a reduction in the synthesis of plasma proteins, particularly,

Classify bones structurally and embryologically, Classify bones structurall...

Classify bones structurally and embryologically(developmentally). Structural classification of bone: Macroscopically can be classified into two types, compact and trabecul

Explain the voges proskauer (vp) test, Explain the Voges Proskauer (VP) Tes...

Explain the Voges Proskauer (VP) Test? As it has been discussed in previous exercise, second group of enteric bacteria produces acid during early incubation which rapidly conve

Explain high fibre diets, High fibre diets High fibre  diets: The pat...

High fibre diets High fibre  diets: The patients  are advised  to  eat  high  fibre cereals as whole grain flour and bread, whole grain bread cereals, whole wheat pasta and b

Munch pressure flow model, Munch Pressure Flow Model Munch, a German p...

Munch Pressure Flow Model Munch, a German plant physiologist, proposed in 1930, a simple physical model which can be tested in the laboratory for the mechanism of phloem trans

Impediments to infuse biology - lack of trained people, Define Impediments ...

Define Impediments to infuse biology - Lack of trained people? At present, biologists as a rule have not been trained sufficiently in quantitative approaches. A heavy dose of m

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