An amino acid pool is the collection of amino acids available in an organism's cells at a given time, based on the proteins and fats recently consumed by the organism. Both plants and animals have amino acid pools, which are replenished whenever the organisms take in nourishment. Amino acids are not stored in cells over long period periods of time, so the makeup of an amino acid pool shifts regularly.
Amino acids are important compounds composed of different chains of four basic molecules: carbon, hydrogen, oxygen and nitrogen. About 500 different amino acids have currently been identified in cells. Each acid helps to maintain the functions of a living organism. For example, the amino acid glutamate, which is found in brain cells, is the main neurotransmitter responsible for conveying electrical impulses through the brain.
Organisms make use of the energy stored in amino acids through a process called catabolism. When an amino acid is catabolized, it breaks down into its component parts, releasing waste and energy that powers the functions of the organism. Once this amino acid has been used, it must be replenished through the introduction of new proteins. These proteins contain slightly different molecules, which leads to the production of slightly different amino acids and an altered amino acid pool.