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

Streptococcal antibody test, In about 80 per cent of ARF patients, ASO titr...

In about 80 per cent of ARF patients, ASO titre is significantly raised. ASO titres vary with age, geographical area and other fevers, which influence frequency of streptococcal in

Explain about the nutritional requirements, Explain about the Nutritional R...

Explain about the Nutritional Requirements? Nutritional requirements are defined as 'intake levels of nutrients that meet specified criteria of adequacy such as normal growth,

Define the management of epileptic patients, Define the Management of Epile...

Define the Management of Epileptic Patients? The primary treatment of epilepsy is anticonvulsant drugs. The focus of nutritional management is a diet, which is appropriate for

State the internal chromosomal segments, Which of the following best explai...

Which of the following best explains the reason why DNA ligase is needed to complete the replication of internal chromosomal segments? A. DNA ligase is able to delete the last

What is peri-implant disease, Q. What is Peri-Implant Disease? The term...

Q. What is Peri-Implant Disease? The term peri-implantitis is used to describe the boneloss around an implant. This may be induced by stress or bacteria or a combination of bot

External factor - factor controlling metamorphosis in insect, External fact...

External factors - Factors Controlling Metamorphosis in Insects In few cases an external factor may be accountable for initiating moulting, as for instance in the blood su

Name the organism included in symbiotic nitrogen fixation, Name the organis...

Name the organism included in symbiotic nitrogen fixation. What are the components needed for this pure? Determine their role. Differentiate among inbreeding and heterosis. The

Explain acid butt - carbohydrate utilization pattern test, Acid butt - carb...

Acid butt - carbohydrate utilization pattern test ? Acid butt (yellow) and acid slant (yellow) with or without gas production – Glucose along with lactose and/or sucrose, is deg

Agro industrial-cobalt, Cobalt Cobalt functions as a component of vitamin ...

Cobalt Cobalt functions as a component of vitamin B12  (cobalamin). Ruminants are not dependent on a dietary source of vitamin B12  because ruminal microorganisms can synthesize B

What is the general function of leukocytes, Q. What is the general function...

Q. What is the general function of leukocytes? What are leukopenia and leukocytosis? The general function of leukocytes is to participate in the made inside the body or defense

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