How are amoebas adapted to live in a hypotonic enviroment?

Answer 1

Amoebae and other protozoa get rid of excess water using organelles called contractile vacuoles. Hypotonic environments cause more water to diffuse into cells than the amount of water that diffuses out of the cells. Contractile vacuoles collect the extra water and "squirt" it back out into the environment. You can see these in action fairly easily in larger paramecia.

Answer 2

the mains ingredient is the bacterial cellular wall which protects the micro organism from "blowing up". different organisms which don't have cellular-wall produce different mechanisms for taking away the surplus water which enters them.