samples. The overall process results in a precise reading of similarities in both similar and different DNA sample. Biochemistry Biochemistry is the science of the chemical processes which takes place within living organisms. Living organisms need essential elements to survive, among which are carbon, hydrogen, nitrogen, oxygen, calcium, and phosphorus. These elements make up the four macromolecules that living organisms need to survive: carbohydrates, lipids, proteins, and nucleic acids. Carbohydrates, made up of carbon, hydrogen, and oxygen, are energy-storing molecules. The simplest carbohydrate is glucose, CHO, is used in cellular respiration to produce ATP, adenosine triphosphate, which supplies cells with energy. Proteins are chains of amino acids that function, among other things, to contract skeletal muscle, as catalysts, as transport molecules, and as storage molecules. Protein catalysts can facilitate biochemical processes by lowering the activation energy of a reaction. Hemoglobins are also proteins, carrying oxygen to an organism's cells. Lipids, also known as fats, are small molecules derived from biochemical subunits from either the ketoacyl or isoprene groups. Creating eight distinct categories: fatty acids, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from condensation of ketoacyl subunits); and sterol lipids and prenol lipids (derived from condensation of isoprene subunits). Their primary purpose is to store energy over the long term. Due to their unique structure, lipids provide more than twice the amount of energy that carbohydrates do. Lipids can also be used as insulation. Moreover, lipids can be used in hormone production to maintain a healthy hormonal balance and provide structure to cell membranes. Nucleic acids are a key component of DNA, the main genetic information-storing substance, found oftentimes in the cell nucleus, and controls the metabolic processes of the cell. DNA consists of two complementary antiparallel strands consisting of varying patterns of nucleotides. RNA is a single strand of DNA, which is transcribed from DNA and used for DNA translation, which is the process for making proteins out of RNA sequences. See also References External links Branches of biology Veterinary medicine Western culture