Endo = enter
This means when things enter into the cell, I hope this helped
Their shells protect them against predators and rough elements. Crabs have tight grips with their pincers, which allows them to grab hold of predators and fend them off. ... Their ability to condense their bodes enables crabs to take cover under rocks and other objects to hide from predators.
A hard outer shell offers protection against predators, in addition to the crab's claws, which they use to hunt prey or fight off predators.
N symbiotic relationship, both the organisms are mutually benefitted. In such a relationship between fungi and lichen, fungi obtain the nutrients being synthesized by the photosynthetic algae.
Algae is offered protection from the environment, by the filaments of the fungi.
The fish gains buoyancy and is able to rise in elevation