Adenosine Tri Phosphate is arguably the most important molecule located within the bodies of human beings. It carries the energy necessary to facilitate all of the processes of human metabolism. The molecule itself is reasonably simple (especially in comparison to the structure of some of the other molecules commonly found in the human body) and consists of an adenine molecule attached to three phosphate molecules (hence the tri phosphate part of the molecular name). The molecular weight of the molecule is around 507 grams of ATP per one mole (a mole is 6.02 x 1023 molecules).


Adenosine Tri Phosphate and Glycolysis


Glycolysis is the first stage of the whole human respiration cycle and the whole process is designed to take a molecule of glucose and transform it into two molecules of pyruvate. Pyruvate molecules are then used as the starting point for the next part of the cycle. The glycolytic pathway relates to the ATP molecule in that during the propagation of the pathway, two new molecules of ATP are created. These ATP molecules are stored for use later on in the respiration cycle but at this point are simply providing an excess of energy heavy molecules within the human body.


Adenosine Tri Phosphate and the Krebs Cycle


The pyruvate molecules created in the previous step then go through the Krebs Cycle (also known sometimes as the citric acid cycle) which in itself produces many more ATP molecules as a side product of the reactions that take place to completely oxidize the pyruvate molecules. By the end of the Krebs cycle, the pyruvate molecules have become completely oxidized into carbon dioxide molecules, which are then expelled out of the body. Other products of these reactions include amongst them ATP molecules, which are absorbed into the mitochondria of a cell and used to power all of the processes of that cell.


Functions of Adenosine Tri Phosphate molecules within a cell


ATP molecules are responsible for a wide range of things within a cell. They are the main energy providers and main fuel for almost any process that goes on in a cell, but some of their more common and important uses are detailed below.


Cell Structure Maintenance: Through various processes, the cell membrane (the outer lining of every human and animal cell) is restructured in order to help protect the cell against intrusion by foreign organisms. In human terms, this can help guard against injuries, illnesses and general fatigue. Whenever the cell membrane or any other structural part of a cell undergoes a restructuring, ATP molecules are consumed to provide the necessary energy.


DNA Synthesis: All living organisms, to the best of our knowledge, contain DNA in them. It is the makeup of these DNA strands that defines who we are and what physical (and to a certain extent emotional) traits we as individuals will possess. Whenever DNA is synthesized inside of the human body, the energy required to do so is provided by the ATP molecules that are present at the time (and that were created through the processes that have already been outlined above).


Intra-Body Signals: Signaling occurs all of the time within the human body. Whether it is a person experiencing pain after touching a hot stove or a person starting to perspire in response to heavy exercise, the sensations are created through signals that permeate throughout our bodies. To facilitate the sending of these signals, ATP molecules are used.




The ATP molecule is one of the most important (if not the most important) molecule that exists in our body. It is designed to be able to provide a large amount of energy for a wide variety of processes. ATP molecules are created primarily through the glycolysis and Krebs Cycle processes and are used in almost every important function that our bodies undertake.