I am a human, a being composed of a lot of different kinds of cells which function as a whole. I have this annoying tendency of constantly respiring, and usually need to consume something of nutritional value multiple times a day. Once night falls, I frequently fall unconscious for long periods of time - which may or may not include somewhat hallucinatory brain activity.
Bio(logy) complete.
In case you can't tell, I'm a bit of a smart-ass on occasion. This is one of those occasions.