Excretory Products And Their Elimination Ques 13
13. In Hydra waste material of food digestion and nitrogenous waste material removed from
(a) mouth and body wall
(b) mouth and tentacles
(c) mouth and nematocyst
(d) body wall and tentacles
Show Answer
Answer : a
Hints & Solutions
(a) Hydra being a coelenterate, has blind sac body plan. It has only one mouth which serves as the opening for ingestion and waste elimination besides diffusion across body wall. The fluid is excreted through a break in the body wall created as a result of a strong contraction when the gut is distended with fluid. A normal hydra, therefore, must remove excess fluid by contracting and expelling it through its mouth.
BETA
