Tonic water added is known as bitter lemon or bitter lime, respectively. The quinine in tonic water will fluoresce under ultraviolet light. In fact, the sensitivity of quinine to ultraviolet light is such that it will appear visibly fluorescent in direct sunlight. Tonic water Tonic water (or Indian tonic water) is a carbonated soft drink in which quinine is dissolved. Originally used as a prophylactic against malaria, tonic water usually now has a significantly lower quinine content and is consumed for its distinctive bitter flavor. It is often used in mixed drinks, particularly in gin and tonic. Quinine was added to the
Tonic (physiology) joint capsule, muscle spindle and the Ruffini corpuscle. Tonic (physiology) Tonic in physiology refers to a physiological response which is slow and may be graded. This term is typically used in opposition to a fast response. For instance, tonic muscles are contrasted by the more typical and much faster twitch muscles, while tonic sensory nerve endings are contrasted to the much faster phasic sensory nerve endings. Tonic muscles are much slower than twitch fibers in terms of time from stimulus to full activation, time to full relaxation upon cessation of stimuli, and maximal shortening velocity. These muscles are rarely found