Some older/less efficient worker termites will develop 'backpacks' of toxic chemicals that explode when the termite is threatened. They are essentially used as suicide bombers when the colony is being attacked.
8
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
It has been estimated that a bite from a grizzly bear can crush a bowling ball.
11
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
132
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6