Q. When a freshwater protozoan, possessing a contractile vacuole, is placed in a glass containing marine water, the vacuole will?
A) Increase in number
B) Disappear
C) Increase in size
D) Decrease in size
Explanation
When freshwater protozoans are placed in marine water, $i.e.,$ hypertonic water, the contractile vacuoles disappear because the process of endosmosis does not happen and thus, water does not come in the protoplasm.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.