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

Skin., what is the difference between fair skin and dark skin?

what is the difference between fair skin and dark skin?

Continuous wave doppler, When a ventricQlar septa1 defect (VSD) is present,...

When a ventricQlar septa1 defect (VSD) is present, with no aortic stenosis, the peak velocitgrĀ  across the defect reflects the difference in pressure between the right ventricle an

Pisces, weberian oscles found in

weberian oscles found in

Potential air pollutants encountered in working environment, Question: ...

Question: a) Why is it important to maintain good standards of Indoor Air Quality in modern offices. Briefly explain the potential air pollutants encountered in such working

Explain the method of recombination or crossing-over, The method of recombi...

The method of recombination or crossing-over Which of the following is a false statement regarding the method of recombination or crossing-over? A. Crossing-over takes place

Define energy and protein requirement in geriatric nutrition, Define Energy...

Define Energy and Protein requirements in geriatric nutrition? Decreased physical activity and changes in body composition and decreased basal metabolic rate affects the ma

Who was gregor mendel, Who was Gregor Mendel? Mendel is considered the ...

Who was Gregor Mendel? Mendel is considered the father of Genetics. He was a monk, biologist and botanist born in Austria in 1822 and who died in 1884. During the years 1853 to

Human ovum, A pair of ovaries are the reproductive organs in woman. They...

A pair of ovaries are the reproductive organs in woman. They are present just below the kidneys in the abdominal cavity. Each ovary has several sac like structures called ova

Discuss in brief about human nose, Nose Nose consists of external and i...

Nose Nose consists of external and internal parts. The inner lining of the nose contains millions of small receptors. These receptors are located on the sensory hairs.

What is hemocoel. explain in detail, What is Hemocoel? Explain in detail. ...

What is Hemocoel? Explain in detail. Principle body cavity in molluscs and arthropods, remnant of the blastocoel. It forms part of open circulatory system found in these animal

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