"Umami" is type of
Ans. c (Taste sensation) (Ref. Ganong Physiology 23rd/pg. Chapter 10, Figure 10-6.)Umami is the fifth taste sense triggered by glutamate and particularly by the monosodium glutamate (MSG) used so extensively in Asian cooking. The taste is pleasant and sweet but differs from the standard sweet taste. The action of umami receptors explains why foods treated with MSG often taste fuller.UMAMI# Humans have five established basic tastes: sweet, sour, bitter, salt, and umami.# Umami is one of the five basic tastes sensed by specialized receptor cells present on the human tongue.# Umami is a Japanese word meaning "savory" or "meaty" and thus applies to the sensation of savoriness--specifically, to the detection of glutamates, which are especially common in meats, cheese and other protein-heavy foods.# Afferent nerves to the nucleus tractus solitarius contain fibers from all types of taste buds, without any clear localization of types.TASTE RECEPTORS# The sour taste is triggered by protons.# Umami taste is due to activation of a truncated metabotopic glutamate receptor, mGluR4, in the taste buds, and the agonists are purine 5-ribonucleotides such as IMP and GMP in the food.# Bitter taste is produced by a variety of unrelated compounds, many of which are poisons. It was originally thought that a single bitter receptor was linked to the heterotrimeric G protein gustducin.# A taste modifier protein, miraculin, has been discovered in a plant. When applied to the tongue, this protein makes acids taste sweet.# A protein that binds taste-producing molecules has been cloned. It is produced by Ebner's glands--glands that secrete mucus into the cleft around vallate papillae and probably have a concentrating and transport function similar to that of the OBP in olfaction.# In humans, the taste buds are located in the mucosa of the epiglottis, palate, and pharynx and in the walls of the fungiform and vallate papillae of the tongue.# The fungiform papillae are rounded structures most numerous near the tip of the tongue; the vallate papillae are prominent structures arranged in a V on the back of the tongue. Each fungiform papilla has up to five taste buds, and they are usually located at the top of the papilla.# The larger vallate papillae each contain up to 100 taste buds, usually located along the sides of the papillae. The small conical filiform papillae that cover the dorsum of the tongue do not usually contain taste buds.# There are a total of about 10,000 taste buds.
Color blindness
Smell sensation
Taste sensation
Deafness
Nervous System