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

What is herbicide tolerant crops in evolutionary, Evolutionary ...

Evolutionary Herbicide tolerant crops (HTC) Increased use of herbicide can result in increase in development of weed resistance to that herbicide either through

Define excretion of toxin and act as precursor- carbohydrate, Define Excret...

Define Excretion of toxins and Act as precursors? Excretion of toxins: Glucuronic acid, a metabolite of glucose, combines with chemical and bacterial toxins and some normal met

Bones, which bone forms the non-moving muscle attachment in the hip joint

which bone forms the non-moving muscle attachment in the hip joint

Metazoan branches, Metazoan Branches The Kingdom Animalia comprises al...

Metazoan Branches The Kingdom Animalia comprises all the multicellular animals (metazoans). These are divided into three branches: Mesozoa Parazoa Eumetazoa

Cell body and cell cycle, Cell body in a neuron, the part which contains t...

Cell body in a neuron, the part which contains the nucleus and most of the cytoplasm and organelles. Cell cycle It is the sequence of events from one division of the cell to

Explain high fibre diets, High fibre diets High fibre  diets: The pat...

High fibre diets High fibre  diets: The patients  are advised  to  eat  high  fibre cereals as whole grain flour and bread, whole grain bread cereals, whole wheat pasta and b

Which is not produced by the hypothalamus, Which of the following is NOT pr...

Which of the following is NOT produced by the hypothalamus? A) releasing hormones B) inhibiting hormones C) antidiuretic hormone D) oxytocin E) thyroid-stimulating h

What is biosynthetic pathways, The intermediates in the cycle give precurso...

The intermediates in the cycle give precursors for various biosynthetic pathways. An instance is as given below: -  From citrate synthesis of fatty acids; -  Amino acid synth

Chromsome, How does a person with drown syndrome obtain a third chromosome ...

How does a person with drown syndrome obtain a third chromosome 21?

Biochemical, Explain the salient features biochemical origin of life.

Explain the salient features biochemical origin of life.

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