GENERAL HISTOLOGY

Detailed explanation-1: -Water vascular system is a unique characteristic of echinoderms. It helps in locomotion, the capture of food and respiration.

Detailed explanation-2: -Echinoderms possess a unique ambulacral or water vascular system, consisting of a central ring canal and radial canals that extend along each arm. Water circulates through these structures and facilitates gaseous exchange as well as nutrition, predation, and locomotion.

Detailed explanation-3: -An echinoderm moves by using many tube feet. Tube feet are small, delicate projections attached along the side of a water-filled tube called a radial canal. Figure 3.85 shows some examples of echinoderm tube feet. Tube feet extend through the small holes in the skeleton to the outside.

Detailed explanation-4: -The water vascular system is used mainly for locomotion. The inner wall of the water vascular canals is provided with cilia. The beating of the cilia causes the seawater to enter through the madreporite. Finally, the seawater reaches the tube feet and their ampulla.

Detailed explanation-5: -Water vascular system is found in Echinoderms. It helps in nutrition, locomotion, respiration, and excretion.-Water enters the water vascular system through a calcareous opening called Madreporite.-Madreporite is connected to a canal-like structure called stone canal.