Adenosine Triphosphate (ATP) I   INTRODUCTION Adenosine Triphosphate or ATP, the main usable energy source found in all living things. ATP fuels most cell activities, including muscle movement, protein synthesis, centriole movement during cell division (see Meiosis; Mitosis), and nerve signal transmission. Most living things need to store energy—plants cannot photosynthesize at night and animals do not spend all of their time feeding, yet the demands of the cells for energy are neverending. ATP is believed to be the main energy-providing and energy-storing molecule for all processes in all cells. Because the energy-exchanging function of ATP and the catalytic (work-boosting) function of enzymes are intimately connected, ATP is also characterized as a coenzyme. II   STRUCTURE ATP is a nucleotide with three phosphate groups attached. In the simple representation of the chemical structure of the molecule, these groups can be seen clearly. In the computer-graphic representation of an ATP molecule, the three phosphate groups are shown in orange. III   ENERGY RELEASE When energy is needed in the cell, the third phosphate bond can be broken in a hydrolysis reaction catalysed by the enzyme ATPase. The result of this hydrolysis is adenosine diphosphate (ADP) and a free inorganic phosphate group (Pi). About 34 kJ (7 kcal) of energy are released per mole of ATP hydrolysed. Some of this energy is lost as heat, but some is also used for energy-requiring biological activities. The release of two phosphate groups from ATP by the enzyme adenyl cyclase forms AMP (adenosine monophosphate), a nucleotide component of nucleic acids, the material of DNA; this enzyme is important in many of the body's reactions. One form of AMP called cyclic AMP, created by the action of the enzyme adenyl cyclase, is instrumental in the activities of many hormones, including adrenaline and ACTH. IV   PRODUCTION OF ATP The breakdown of ATP into ADP and inorganic phosphate is a reversible reaction. Usually, ADP quickly regains the third phosphate unit through the action of cytochrome, a protein that builds it up by using food energy. Catabolic reactions—for example, the breakdown of glucose during cellular respiration in both plants and animals—can be coupled to the synthesis of molecules of ATP from ADP and phosphate groups. This reaction is also catalysed by ATPase. Energy is thus stored in the ATP molecule, ready for use when required in anabolic reactions (see Metabolism). In vertebrate muscle and brain cells, excess ATP can join with creatine to provide a reserve energy store. The main site of ATP production in the cell is in the mitochondria, where the ATPase enzyme is sited on the folded inner membranes. The process by which ATP is made is universal, appropriately for the molecule believed to be the universal energy supplier for all living cells. Plants produce ATP by direct utilization of the energy in sunlight, that is, through photosynthesis.   Francis Leroy, Biocosmos/Science Source/Photo Researchers, Inc. Computer-Generated Structure of Adenosine Triphosphate Adenosine Triphosphate (ATP) is the main usable energy source found in all living things. ATP fuels most cell activities, including muscle movement, protein synthesis, cell division, and nerve signal transmission. In this computer-graphic representation of an ATP molecule, the three phosphate groups, in the bonds of which ATP’s energy is stored, are shown in orange. Mitochondria INTRODUCTION Mitochondria, generally physically independent substructures, one of several types of organelle (cell organ), found in almost all eukaryotic cells where they perform important functions, especially respiration and provision of energy in a form that cells can use. Mitochondria Mitochondria, minute sausage-shaped structures found in the hyaloplasm (clear cytoplasm) of the cell, are responsible for energy production. Mitochondria contain enzymes that help to convert food material into adenosine triphosphate (ATP), which can be used directly by the cell as an energy source. Mitochondria tend to be concentrated near cellular structures that require large inputs of energy, such as the flagellum, which is responsible for movement in vertebrate sperm cells and single-celled plants and animals.Don Fawcett-Keith Porter/Photo Researchers, Inc. The name mitochondria comes from two Greek words, “mito” meaning “filaments” and “chondros” meaning “grains”, which were used in the 19th century to describe the appearance of parts of cells under the light microscope. The number of mitochondria per cell may depend on the cell type. It was thought for a long time that a cell contained many (even thousands or more) mitochondria, typically sausage-shaped and of a similar size to bacteria, which were located independently of other cell components. Currently it is thought that, at least in some cells, the mitochondria comprise a largely connected and continuous single network which can sometimes interact with a second type of organelle, the endoplasmic reticulum. The extent to which there are many independent mitochondria in any given cell type, as accepted for many years and suggested by looking with a technique called electron microscopy at sections of cells, is currently being evaluated. Don Fawcett-Keith Porter/Photo Researchers, Inc. Mitochondria Mitochondria, minute sausage-shaped structures found in the hyaloplasm (clear cytoplasm) of the cell, are responsible for energy production. Mitochondria contain enzymes that help to convert food material into adenosine triphosphate (ATP), which can be used directly by the cell as an energy source. Mitochondria tend to be concentrated near cellular structures that require large inputs of energy, such as the flagellum, which is responsible for movement in vertebrate sperm cells and single-celled plants and animals. Recommended Physician's Reference Book: How to achieve Super Health beyond 2000 - By Frank D.P. Ellis & Dr. Michael Tait M.D    Published By: Superlife Products Ltd.      Begin the Journey to Total Wellness & Peak Performance