Locomotion in echinodermata, Biology

Assignment Help:

Locomotion in Echinodermata

Locomotion in echinoderms is accomplished through a unique canalicular system which is termed as the water-vascular system. This system is characteristic of echinoderms, in most of that it is quite well developed. It consists of a series of canals derived from the coelom. The canals consist of a fluid. Sea water has free access to the system via a perforated sieve plate called the madreporite on the aboral side of the animal. The fluid is much more like seawater but has a high content of potassium ions. Some proteins and several types of amoebocytes float in it. The structural organisation of the water-vascular system is chiefly the same in all echinoderms, though deviations from the basic plan occur. To study the components of the system, we might take the water-vascular system of the star-fish, as typical example. Its main component applicable from the point of view of locomotion consists of a pentagonal circumoral vessel that is termed as the ambulacral ring canal. From the ring canal are given off five radial vessels. Every radial canal extends up to the tip of the arm. It gives off a large number of side vessels along its course. Each side vessel leads into a tube-foot or podium, which is a hollow conical or cylindrical process with an ampulla and a terminal sucker. A Valve is present at the junction of lateral vessel with the tube-foot.


Related Discussions:- Locomotion in echinodermata

Nutritional management for diarrhoea, Q. Nutritional management for diarrho...

Q. Nutritional management for diarrhoea? The conservative concept of treatment for diarrhoea was not in favour of feeding adequate amount of food. However, with the identificat

Modes of nitrate reductase and nitrite reductase, Modes of NO - 3 reducti...

Modes of NO - 3 reduction Accordingly, there are the following three basic modes of NO - 3 reduction. Directly dependent upon photosynthesis as in cyanobacter

Define the nutritional needs of microorganisms, Define the Nutritional Need...

Define the Nutritional Needs of Microorganisms? About 95% of dry cell weight of microorganisms is constituted by macro elements. These are carbon (C), nitrogen (N), oxygen (O),

What do you mean by alpha taxonomy, Q. What do you mean by Alpha Taxonomy? ...

Q. What do you mean by Alpha Taxonomy? This relates to the basic or preliminary classification based almost entirely on external morphology. This can be considered as the empir

Nitrogen fixation, Nitrogen Fixation Nitrogen is an essential constitue...

Nitrogen Fixation Nitrogen is an essential constituent of living organisms and there is an inexhaustible supply of it in the atmosphere in the free form. Majority of living o

Admission procedure - nursing, Admission Procedure   From the time  the...

Admission Procedure   From the time  the child and his family enter the hospital doors, the admission procedure should be carried out in a friendly and efficient manner. Admiss

Define absorption, Define Absorption, Storage and Elimination of Pyridoxine...

Define Absorption, Storage and Elimination of Pyridoxine? Pyridoxine, pyridoxal and pyridoxamine (along with their phosphorylated forms) occur in plant and animal foods. The ph

Evolution, related words for reproductive isolation.

related words for reproductive isolation.

What are the main techniques of genetic engineering, At the present level o...

At the present level of the biotechnology what are the main techniques of genetic engineering? The major techniques of genetic engineering today are: the recombinant DNA techno

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