Question: 166. Role of the water vascular system in Echinoderms is:
A. Respiration and Locomotion
B. Excretion and Locomotion
C. Capture and transport of food
D. Digestion and Respiration
E. Digestion and Excretion
Choose the correct answer from the options given below:
(1) A and B Only
(2) A and C Only
(3) B and C Only
(4) B, D and E Only
Answer: Option (2)
Explanation:
The water vascular system is a characteristic feature of echinoderms such as starfish and sea urchins.
It is a hydraulic system consisting of canals and tube feet filled with water.
The primary function of the water vascular system is locomotion, which is achieved by the extension and contraction of tube feet.
The tube feet also help in respiration by allowing gaseous exchange through their thin walls.
In many echinoderms, the tube feet are involved in capture and transport of food towards the mouth.
The water vascular system does not play a role in digestion or excretion.
Therefore, the correct roles are respiration and locomotion (A) and capture and transport of food (C).
Hence, the correct answer is Option (2).