How venom works
Animal venom reacts with a molecule called histamine. Histamine is a nitrogen compound with a molecular formula of C5H9N3 and is found in most mammal's immune systems. When histamine reacts, it can release a suppressive effect which causes immune system disorders.
Some examples of animals with venom
Portuguese Man O' War
Can still poison for hours or days after dying
A sliced off jellyfish tentacle poisoned 150 people in New Hampshire
One of the only venomous mammals