Mitochondria are the energy factories of the cells. The energy currency for the work that animals must do is the energy-rich molecule adenosine triphosphate (ATP). The ATP is produced in the mitochondria using energy stored in food. This is a very efficient process for using food energy to make ATP.

In the mitochondria, the metabolism of sugars is completed, and the energy released is harnessed so efficiently that about 30 molecules of ATP are produced for each molecule of glucose oxidized.

Cellular respiration takes in food and uses it to create ATP, a chemical which the cell uses for energy. Usually, this process uses oxygen, and is called aerobic respiration. This produces ATP which supplies the energy that cells need to do work.

Most of the ATP produced by aerobic cellular respiration is made by oxidative phosphorylation. Biology textbooks often state that 38 ATP molecules can be made per oxidized glucose molecule during cellular respiration (2 from glycolysis, 2 from the Krebs cycle, and about 34 from the electron transport system).

mitochondria

The Immediate Energy system, or ATP-PC, is the system the body uses to generate immediate energy. The energy source, phosphocreatine (PC), is stored within the tissues of the body. When exercise is done and energy is expended, PC is used to replenish ATP.

ATP synthase

nucleic acids

ATP – Nature’s Energy Store proteins and DNA, and the transport of molecules and ions throughout the organism. Other processes occur only at certain times, such as muscle contraction and other cellular movements.

ATP synthesis involves the transfer of electrons from the intermembrane space, through the inner membrane, back to the matrix. The combination of the two components provides sufficient energy for ATP to be made by the multienzyme Complex V of the mitochondrion, more generally known as ATP synthase.