November 30, 2013

Energy efficiency of human machine

Living organisms require energy for every activity they perform. As I am keying in from the keyboard, energy is being used for movement of fingers, thought and coordination processes running in the brain. The immediate source of this energy in heterotrophic organisms, which include animals, fungi, and most bacteria, is the sugar glucose. Glucose is oxidized into carbon dioxide and water with the help of inhaled oxygen and in the process 2880 KJ/mol energy is released. Of course it would not do to simply “burn” the glucose in the normal way; the energy change would be wasted as heat, and… Read More »Energy efficiency of human machine