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

What is ocean shorelines, Q. What is Ocean shorelines? Ocean shorelines...

Q. What is Ocean shorelines? Ocean shorelines include rocky coasts and sandy beaches that are particularly rich in diverse life forms. Rocky shorelines support a diversity of o

What is an immunotoxin, Immunotoxin is formed by conjugating or combining a...

Immunotoxin is formed by conjugating or combining an antibody with highly toxic agent.

Subphylum mastigophora, Subphylum Mastigophora One or more flagella p...

Subphylum Mastigophora One or more flagella present in adult stages; autotrophic or heterotrophic nutrition; reproduction usually asexual by fission. Class - Phytomasti

What does acute disease mean, What does acute disease mean? An sharp di...

What does acute disease mean? An sharp disease is which does not last for a longer duration n has no weakness in the body

Sulphur cycle, Sulphur is one of important of proteins vitamins and hormone...

Sulphur is one of important of proteins vitamins and hormones. It plays a very crucial role in health of both plants and animals. Most of earth sulphur is tied up in rocks and salt

What factor contributed to the current variations, According to the theory ...

According to the theory of natural selection, what factor below contributed to the current variations in beak sizes of finch species on the Galapagos Islands? a. Finches dispersed

Estimation of protein by availability of amino acids include, Estimation of...

Estimation of protein by Availability of amino acids include? Regeneration of blood and liver constituents includes Liver protein regeneration Blood protein regener

Where are the adrenal glands located, Q. Where are the adrenal glands locat...

Q. Where are the adrenal glands located? How many are they and what are their portions? Each adrenal gland is located on the top of each kidney (forming a hat-like structure fo

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