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 are the major bone surfaces, Bone Surfaces:  There are four major bon...

Bone Surfaces:  There are four major bone surfaces: 1) Periosteal (outer surface of all bones) 2) Endosteal (inner surface of cortical bone) 3) Haversian (inner surface o

Structure of golgi body, STRUCTURE Golgi body consists of :- (1 ) ...

STRUCTURE Golgi body consists of :- (1 ) Cisternae These are plate like unbranched structure with dilated ends. One golgi body has 4-8 cisternae. Mono cisternal

Photoreceptors, Photoreceptors Photoreceptors are concerned in absorpt...

Photoreceptors Photoreceptors are concerned in absorption of light by photosensitive pigments. The chemical change involved produces the impulse concerned in the nerve cells.

Guidelines for the family members for healthy coping, Q. Guidelines for the...

Q. Guidelines for the Family Members for Healthy Coping? - Patient and the family members should discuss the situation, change in role,time distribution, share of money and oth

Define oral rehydration for treatment for pem, Define Oral rehydration for ...

Define Oral rehydration for treatment for pem? Since diarrhoea is very common in severe PEM, correction of dehydration is the first step in the treatment. Homemade (salt-sugar

Preserving foods, One of man's oldest methods of preserving foods is drying...

One of man's oldest methods of preserving foods is drying or desiccation. The preservation of foods by drying is a direct result of removal of moisture. Microorganisms need water

Demographic cycle, DEMOGRAPHIC CYCLE - 1 .       First stage - B...

DEMOGRAPHIC CYCLE - 1 .       First stage - B high     - D high     =  0 2 .       Second stage - B high     - D lo w     =  G more eg.

Parasitic diseases - fascioliasis, P a r a s i t i c Diseases ...

P a r a s i t i c Diseases F a s cioliasis It is a liverfluke infestation characterized by hepatic insufficiency, bile duct obstruction, and poor production per

Why nutrition is important for health, Why Nutrition is important for healt...

Why Nutrition is important for health Nutrition is one of the basic components of  life. It is an essential part of health care. You already know that good nutrition  is essent

Explain the composition of macconkey agar, Explain the Composition of MacCo...

Explain the Composition of MacConkey Agar? Bactopeptone - 17.0 gm Protease Peptone - 3.0 gm Lactose - 10.0 gm Bile salt mixture - 1.5 gm Sodium chloride - 5.0 gm

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