Intravenous Injection of Chemotherapy. It is very common for chemotherapy medications to be injected into a vein, or intravenously. In many cases, a nurse or doctor will insert a needle into your vein, often in your hand or arm, and the chemotherapy will be given through there.
2. Poison Dart Frog. Of all the poisonous animals in the world, these are probably the easiest to spot due to their extremely bright colors, including yellow, blue, green, & red. These frogs don't actually inject their poison through their mouth; they do it through their skin.
Without a doubt, the most dangerous animal in the world is the face you see in the mirror each day. Nonetheless, caught off our guard, it is easy for any of the animals on this list to overcome us. All it takes is one misstep on the sea floor, or a really angry buffalo.