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

Name the two hormones produced by the pancreas, Name the two hormones produ...

Name the two hormones produced by the pancreas and say (a) in what circumstances, (b) in what way, they adjust the glucose concentration in the blood.

Explain intensity of heart sound, Explain Intensity of heart sound? Int...

Explain Intensity of heart sound? Intensity of S 1, particularly M 1 depends on the position of the bellies of mitral leafets when the LV begins to contract since S 1 is loudes

Define the term- species, What is a species? A species is a set of livi...

What is a species? A species is a set of living beings able to cross between themselves generating fertile offspring. This concept though does not apply to individuals of ex

Illustrate the maturation of honey, Q. Illustrate the maturation of honey? ...

Q. Illustrate the maturation of honey? Honey is the oldest sweet food known to man. Although honey is a natural sweetener, it is considered a refined sugar because 96% of dr

Distribution coefficient -terminology used in chromatography, Distribution ...

Distribution Coefficient - Terminologies used in Chromatography? During the purification or separation of the biomolecules it should be kept in mind that two important factors

Define about the excretion of calcium, Define about the Excretion of Calciu...

Define about the Excretion of Calcium? Calcium is excreted approximately in equal amounts in urine and through intestinal secretions. Bile and other secretions into the intest

Microscopy, describe the importance,principles,techniques and uses of micro...

describe the importance,principles,techniques and uses of microscopy

Sensor measures the current value of the controlled variable, In a properly...

In a properly functioning negative feedback system A. value of the controlled variable will always be very close to the threshold value when the system is in steady state.

Diabetic foot are impaired blood supply to foot, Diabetic foot are impaired...

Diabetic foot are impaired blood supply to foot Diabetic foot are impaired blood supply to foot i.e. vasculopathy. This leads to ischaemia which in turn leads to delayed or non

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