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 do you understand by amphid, What do you Understand by Amphid? Uni...

What do you Understand by Amphid? Unique to the nematodes, these paired sensory structures are located on the sides of the head. An external pore leads to an inner chamber and

Patient after cardiac transplant, Patient after cardiac transplant ...

Patient after cardiac transplant The major focus of medical and nursing care after transplantation is to prevent early identification of rejection so that appropriate

Spleen, SPLEEN Largest lymph gland, also with myeloid tissue is an i...

SPLEEN Largest lymph gland, also with myeloid tissue is an important specialized reticuloendothelial organ in vertebrates, as the site of erythropoiesis. Splenic tissue i

Patterns of cleavage, P A TTERNS OF CLEAVAGE - Patterns of cleavage d...

P A TTERNS OF CLEAVAGE - Patterns of cleavage depends upon amount of yolk & distribution of yolk. These are following types - 1 .       RADIAL CLEAVAGE PATTERN -

Write the derivation of michaelis-menten model equation, 1. Briefly explain...

1. Briefly explain the dynamics in enzyme reaction mechanism with potential energy surface diagram. 2. How to find the rate constant of any enzymetic reaction? 3. Derivation

Explain the process of transposition of the great arteries, Transposition o...

Transposition of the Great Arteries with VSD and Left Ventricular Outflow Tract Obstruction: The presence of such a condition has to be surgically corrected title is differenc

Explain uristix benedicts test, Q. Explain Uristix Benedicts test? No s...

Q. Explain Uristix Benedicts test? No sugar/glucose is excreted in the urine in normal individuals. In diabetics, glucose is excreted by the kidneys when the blood sugar levels

Zoonoses disease-vaccinia-like disease, Vaccinia-like disease Smallpox caus...

Vaccinia-like disease Smallpox caused by variola virus (VARV) has successfully been eradicated in the last quarter of the 20th century. However, vaccinia like viruses (VLVs) , viz.

How to reduce the stresses on the implant, How to reduce the stresses on th...

How to reduce the stresses on the implant i) There is need to reduce the stresses on the implant - ii) Frequent recall for maintenance or hygiene appointments. iii) Gingi

Amoebas, two types of amoebas waste and how they get rid of them

two types of amoebas waste and how they get rid of them

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