#biochemistry

• Arginase — A highly crucial hydrolytic enzyme, primarily located in the cytoplasm of hepatocytes, which catalyzes the final phase of the urea cycle. This structural biocatalyst splits arginine into ornithine and urea, facilitating the efficient elimination of toxic ammonia resulting from protein metabolism and thus preventing severe neurological disorders.
• Arginine — A vital semi-essential amino acid for the human body, structurally involved in protein synthesis, ammonia detoxification via the urea cycle, and nitric oxide production. This organic compound plays a crucial role in blood pressure regulation, immune system support, wound healing, and hormone secretion, frequently administered as a dietary supplement in sports nutrition and cardiovascular therapies.
• RNA — Acronym for Ribonucleic Acid (RNA); a polymeric molecule essential in various biological roles in coding, decoding, regulation, and expression of genes. Structurally a single strand containing ribose, phosphate, and nitrogenous bases.
• Ascorbic — Relating to or belonging to ascorbic acid; a term used almost exclusively within the phrase 'ascorbic acid', which represents the official chemical name for Vitamin C. It is a water-soluble organic compound with potent antioxidant properties, holding a vital structural role in collagen synthesis, immune system function, iron absorption, and the prevention of scurvy.
• Ascorbicuria — The presence or excretion of a measurable amount of ascorbic acid (vitamin C) in the urine. In a clinical and biochemical sense, monitoring this urinary parameter is used to evaluate the body's saturation level with water-soluble vitamins, identify nutritional deficiency states, or detect secondary hyperoxaluria induced by megadoses.
• Ascorbinemia — The presence and concentration of ascorbic acid (vitamin C) in the circulating blood. In a clinical context, the analysis of this plasma value is essential for establishing a patient's true nutritional status, evaluating the total antioxidant capacity of the serum, and diagnosing early severe hypovitaminosis.
• Stunning agent — Causing or producing stunning; (as a neuter noun) a chemical substance, gas mixture, or anesthetic agent used in industrial or clinical settings to rapidly induce temporary unconsciousness and structural insensitivity to pain in animals.
• Asparagine — A non-essential amino acid, being the first one historically isolated from natural sources (asparagus juice in 1806); it plays a crucial role in human protein biosynthesis, central nervous system metabolism as a neurotransmitter precursor, and in the clearance of toxic ammonia from the body via urea transformation; it is also a key structural compound in the nitrogen metabolism of many higher plants.
• Aspartame — An intense, low-calorie artificial sweetener, synthetically produced by combining two natural amino acids: aspartic acid and phenylalanine; widely used in the global food industry as a sugar substitute under the European code E951. This organic compound is approximately 200 times sweeter than sucrose, frequently integrated into diet carbonated beverages, confectionery products, and foods intended for individuals with diabetes.
• Aspartic — Containing aspartate or relating to a non-essential dicarboxylic amino acid; used almost exclusively in the phrase 'aspartic acid', a fundamental constituent of human and animal proteins that plays a vital role in the urea cycle, the synthesis of other amino acids, and the proper functioning of the metabolic and nervous systems.
• Atax — A specialized term used in various technical and medical fields. In biochemistry and medicine, it is encountered as a truncated variant, prefix, or non-standard acronym referring to taxine or phenomena related to ataxia (lack of coordination of muscle movements). In information technology, it can designate a specific command, software utility, or process identifier within certain operating systems.
• Autoantigen — A normal molecular constituent, macromolecule, protein, or cellular structure native to an organism that, under conditions of impaired immune tolerance, is erroneously recognized as a foreign substance (antigen) and becomes the target of an attack triggered by its own immune system.
• Self-dissolution — The act of self-dissolving and its result; an autonomous physical-chemical process of degradation and liquefaction of a substance, or a political act whereby a collective body (parliament, committee, association) ceases its legal existence by its own will.
• Autolytic — Pertaining to or involving autolysis; that destroys, decomposes, or digests its own cells or tissues via intracellular enzymes (such as lysosomal ones) released after cell death or during programmed physiological processes. In biochemistry and histopathology, the term describes an intrinsic self-destructive process, essential in necrosis, apoptosis, or in the post-mortem degradation of biological samples that were not fixed properly in time.
• Autolysis — A spontaneous and aseptic biological process of self-destruction, decomposition, or digestion of animal or vegetable cells and tissues, carried out by their own intracellular enzymes (especially lysosomal hydrolases) released following cell death or metabolic arrest. In forensic medicine, it represents the first stage of post-mortem decay, while in food biochemistry, it is a controlled phenomenon essential for meat aging or yeast fermentation.
• Autolysin — An enzymatic substance (hydrolase) produced by a bacterial or animal cell, capable of dissolving or decomposing the membrane, cell wall, or internal biological structures of the organism that secreted it. In microbiology, these specific enzymes control cell division, peptidoglycan wall remodeling, and spontaneous bacterial lysis during the decline phase of a cellular culture.
• Autoxidation — A spontaneous and slow oxidation chemical reaction of a substance (such as fatty acids, oils, polymers, or organic compounds) that occurs upon direct contact with molecular oxygen in the air at ordinary temperatures and without the intervention of a strong oxidizing agent or a flame. This structural autocatalytic process involves the formation of free radicals and peroxides, being responsible for food rancidity, rubber degradation, or biological tissue aging.
• Autoproteolysis — A biochemical process of spontaneous and autonomous cleavage, degradation, or enzymatic digestion of proteins within a cell or organic tissue, executed by the organism's own proteolytic enzymes (proteases, peptidases). This endogenous structural phenomenon occurs in a controlled manner during autophagy and cellular turnover, but can be triggered destructively and uncontrollably in pathological states of ischemia, acute inflammation, or immediately following cell death (post-mortem necrosis).
• Self-sterilization — The act of self-sterilizing and its result; an autonomous physical, chemical, or biological process through which a surface, smart material, or device destroys bacteria, viruses, and other microorganisms without direct external intervention. It also refers to the automatic function of modern medical devices (such as autoclaves or incubators) to run internal total decontamination programs at the end of their operating cycle.
• Auxin — A plant hormone (phytohormone) secreted by the apical meristematic tissues of plants, possessing the fundamental property of stimulating cell elongation, root initiation, fruit development, and the orientation of plant tropisms; indole-3-acetic acid is the most common natural representative of this class.