The sense of taste cells in the mouth, with each taste bud containing receptor cells in contact with afferent nerves.
Several afferent nerves innervate a single taste bud, while a single efferent fiber innervates several taste buds.
Taste buds are composed of four different types of cells, and each taste bud has at least 30 to 80 cells.
Taste buds are mainly on the upper surface of the tongue.
The function of taste perception is vital to help prevent harmful or rotten foods from being consumed.
Taste buds are also present on the epiglottis and upper part of the esophagus.
Type I cells are thinly shaped, primarily in the periphery of other cells.
Type II cells have prominent nuclei and nucleoli with much less chromatin than Type I cells.
Type III cells have multiple mitochondria and large vesicles.
Type I, II, and III cells also contain synapses.
Type IV cells are normally rooted at the posterior end of the taste bud.
Every cell in the taste bud forms microvilli at the ends.
Fungiform papillae are present on the anterior portion of the tongue.
Circumvallate papillae and foliate papillae are found on the posterior portion of the tongue.
The salivary glands keep the taste buds moist with saliva.
Taste buds are present in the mouth, throat, larynx, and esophagus and are replaced every ten days.
Ovoid bodies that measure 50-70 microm.
Made up of four cell types: basal, type 1 and 2, and 3.
Type 1 and 2 cells are sustenacular cells and type 3 ells are the gustatory receptors cell that make synaptic connections in sensory nerve fibers.
Type 3 cells have a microvillus that projects into the taste pore, an opening to the oral cavity.
Taste receptors for sweetness TIR2/R1R3.
Taste receptors for sweetness can detect sugar at a concentration as low as 1 part in 200.
Bitter substances can be detected in the range of a few parts per million.
Innate preference for sweetness exists.
The taste buds are innervated by a branch of the facial nerve the chorda tympani, and the glossopharyngeal nerve.
Taste messages are sent via these cranial nerves to the brain.
The brain can distinguish between the chemical qualities of the food.
The five basic tastes are referred to as those of saltiness, sourness, bitterness, sweetness, and umami.
The detection of saltiness and sourness enables the control of salt and acid balance.
The detection of bitterness warns of poisons.as many of a plant’s defenses are of poisonous compounds that are bitter.
Sweetness guides to those foods that will supply energy; the initial breakdown of the energy-giving carbohydrates by salivary amylase creates the taste of sweetness since simple sugars are the first result.
The taste of umami is thought to signal protein-rich food.
Sour tastes are acidic which is often found in bad food.
Olfactory receptors are located on cell surfaces in the nose which bind to chemicals enabling the detection of smells.
It is assumed that signals from taste receptors work together with those from the nose, to form an idea of complex food flavors.