Taste: The ability to detect chemicals through gustatory receptors in the mouth, including those on the TONGUE; the PALATE; the PHARYNX; and the EPIGLOTTIS.Taste Buds: Small sensory organs which contain gustatory receptor cells, basal cells, and supporting cells. Taste buds in humans are found in the epithelia of the tongue, palate, and pharynx. They are innervated by the CHORDA TYMPANI NERVE (a branch of the facial nerve) and the GLOSSOPHARYNGEAL NERVE.Taste Perception: The process by which the nature and meaning of gustatory stimuli are recognized and interpreted by the brain. The four basic classes of taste perception are salty, sweet, bitter, and sour.Taste Disorders: Conditions characterized by an alteration in gustatory function or perception. Taste disorders are frequently associated with OLFACTION DISORDERS. Additional potential etiologies include METABOLIC DISEASES; DRUG TOXICITY; and taste pathway disorders (e.g., TASTE BUD diseases; FACIAL NERVE DISEASES; GLOSSOPHARYNGEAL NERVE DISEASES; and BRAIN STEM diseases).Taste Threshold: The minimum concentration at which taste sensitivity to a particular substance or food can be perceived.Chorda Tympani Nerve: A branch of the facial (7th cranial) nerve which passes through the middle ear and continues through the petrotympanic fissure. The chorda tympani nerve carries taste sensation from the anterior two-thirds of the tongue and conveys parasympathetic efferents to the salivary glands.Sweetening Agents: Substances that sweeten food, beverages, medications, etc., such as sugar, saccharine or other low-calorie synthetic products. (From Random House Unabridged Dictionary, 2d ed)Saccharin: Flavoring agent and non-nutritive sweetener.Quinine: An alkaloid derived from the bark of the cinchona tree. It is used as an antimalarial drug, and is the active ingredient in extracts of the cinchona that have been used for that purpose since before 1633. Quinine is also a mild antipyretic and analgesic and has been used in common cold preparations for that purpose. It was used commonly and as a bitter and flavoring agent, and is still useful for the treatment of babesiosis. Quinine is also useful in some muscular disorders, especially nocturnal leg cramps and myotonia congenita, because of its direct effects on muscle membrane and sodium channels. The mechanisms of its antimalarial effects are not well understood.Sodium Glutamate: One of the FLAVORING AGENTS used to impart a meat-like flavor.Food Preferences: The selection of one food over another.Sucrose: A nonreducing disaccharide composed of GLUCOSE and FRUCTOSE linked via their anomeric carbons. It is obtained commercially from SUGARCANE, sugar beet (BETA VULGARIS), and other plants and used extensively as a food and a sweetener.Dysgeusia: A condition characterized by alterations of the sense of taste which may range from mild to severe, including gross distortions of taste quality.Ageusia: Complete or severe loss of the subjective sense of taste, frequently accompanied by OLFACTION DISORDERS.Flavoring Agents: Substances added to foods and medicine to improve the quality of taste.Citric Acid: A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium chelating ability.Receptors, G-Protein-Coupled: The largest family of cell surface receptors involved in SIGNAL TRANSDUCTION. They share a common structure and signal through HETEROTRIMERIC G-PROTEINS.Transducin: A heterotrimeric GTP-binding protein that mediates the light activation signal from photolyzed rhodopsin to cyclic GMP phosphodiesterase and is pivotal in the visual excitation process. Activation of rhodopsin on the outer membrane of rod and cone cells causes GTP to bind to transducin followed by dissociation of the alpha subunit-GTP complex from the beta/gamma subunits of transducin. The alpha subunit-GTP complex activates the cyclic GMP phosphodiesterase which catalyzes the hydrolysis of cyclic GMP to 5'-GMP. This leads to closure of the sodium and calcium channels and therefore hyperpolarization of the rod cells. EC 3.6.1.-.Avoidance Learning: A response to a cue that is instrumental in avoiding a noxious experience.PhenylthioureaSodium Chloride: A ubiquitous sodium salt that is commonly used to season food.Geniculate Ganglion: The sensory ganglion of the facial (7th cranial) nerve. The geniculate ganglion cells send central processes to the brain stem and peripheral processes to the taste buds in the anterior tongue, the soft palate, and the skin of the external auditory meatus and the mastoid process.Phospholipase C beta: A phosphoinositide phospholipase C subtype that is primarily regulated by its association with HETEROTRIMERIC G-PROTEINS. It is structurally related to PHOSPHOLIPASE C DELTA with the addition of C-terminal extension of 400 residues.Inosine Monophosphate: Inosine 5'-Monophosphate. A purine nucleotide which has hypoxanthine as the base and one phosphate group esterified to the sugar moiety.Lithium Chloride: A salt of lithium that has been used experimentally as an immunomodulator.Drinking Behavior: Behaviors associated with the ingesting of water and other liquids; includes rhythmic patterns of drinking (time intervals - onset and duration), frequency and satiety.Chemoreceptor Cells: Cells specialized to detect chemical substances and relay that information centrally in the nervous system. Chemoreceptor cells may monitor external stimuli, as in TASTE and OLFACTION, or internal stimuli, such as the concentrations of OXYGEN and CARBON DIOXIDE in the blood.Aspartame: Flavoring agent sweeter than sugar, metabolized as PHENYLALANINE and ASPARTIC ACID.Stimulation, Chemical: The increase in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.TRPM Cation Channels: A subgroup of TRP cation channels named after melastatin protein. They have the TRP domain but lack ANKYRIN repeats. Enzyme domains in the C-terminus leads to them being called chanzymes.Necturus: A genus of the Proteidae family with five recognized species, which inhabit the Atlantic and Gulf drainages.Conditioning (Psychology): A general term referring to the learning of some particular response.Propylthiouracil: A thiourea antithyroid agent. Propythiouracil inhibits the synthesis of thyroxine and inhibits the peripheral conversion of throxine to tri-iodothyronine. It is used in the treatment of hyperthyroidism. (From Martindale, The Extra Pharmacopeoia, 30th ed, p534)Smell: The ability to detect scents or odors, such as the function of OLFACTORY RECEPTOR NEURONS.Feeding Behavior: Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.Amiloride: A pyrazine compound inhibiting SODIUM reabsorption through SODIUM CHANNELS in renal EPITHELIAL CELLS. This inhibition creates a negative potential in the luminal membranes of principal cells, located in the distal convoluted tubule and collecting duct. Negative potential reduces secretion of potassium and hydrogen ions. Amiloride is used in conjunction with DIURETICS to spare POTASSIUM loss. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p705)Cyclamates: Salts and esters of cyclamic acid.