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

Describe the functionality of implant material, Functionality of implant ma...

Functionality of implant material It should take maximum advantage of available bone and permit the maximum amount of forces to be transmitted through the implant within physio

Plant classfication, why obelia is considered to be of special interest in ...

why obelia is considered to be of special interest in zoology as an animal showing an intermediate grade of organisation

Malaria, what are the etiological agents of malaria

what are the etiological agents of malaria

Explain about the cyclamate - artificial sweeteners, Explain about the cycl...

Explain about the cyclamate - artificial sweeteners? Another sweetener is cyclamate (sodium cyclohexylsulphamate). Have a look at its structure as shown in the figure. It is on

Does the fish heart pump venous or arterial blood, Does the fish heart pump...

Does the fish heart pump venous or arterial blood? The venous blood coming from the tissues enters the atrium and passes to the ventricle that then pumps the blood towards the

Types of surgery, Types of Surgery :  Tricuspid valvotomy is done as an op...

Types of Surgery :  Tricuspid valvotomy is done as an open procedure at the end of surgery on mitral and/or aortic valve. It can be done on an arrested heart or on a beating heart

What are the processes that autotrophic beings, What are the processes that...

What are the processes that autotrophic beings use to produce organic material from inorganic substances? The Autotrophic beings make organic material by photosynthesis or by c

Animals - rapidly flowing waters, Animals - Rapidly Flowing Waters In ...

Animals - Rapidly Flowing Waters In the exposed rock surface habitats only those organisms are found which have efficient mechanisms for staying in one place. In fact despite

Discuss the presence and occurrence of lactase persistence, Lactase non-per...

Lactase non-persistence is an example of a genetic trait that has been influenced by cultural factors.Domestication of animals by humans began approximately 10  000 years ago. Farm

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