L3-Tongue

Question 1

What type of epithelium is found in the mucosa covering the dorsal surface of the tongue?

Answer 1

Stratified squamous epithelium. Has muccosal projections called lingual papillae.

Question 2

What are the three lingual papillae with taste buds and what is the one without?

Answer 2

With = Circumvallate, fungiform, and foliate papillae
Without = Filiform

Question 3

Taste buds on the papillae are barrel-shaped epithelial structures that contain what type of sensory cells?

Answer 3

Chemo-sensory cells.

Question 4

What 3 (broad) locations are taste buds found in?

Answer 4

1. Stratified squamous epithelium of lingual papillae
2. Oral mucosa
3. Upper esophagus

Question 5

What are the 4/5 taste sensations and what are their possible functions?

Answer 5

1) Bitter: Structurally diverse, function to detect and avoid toxins.
2 & 3) Sweet and Umami (the fifth taste sensation ~savory): Heterodimers and share a single protein. Function to detect calorically-rich and essential nutrients.
4) Sour: Along with salty has Ion channel for transduction of signals. Function to avoid spoiled food.
5) Salty: Along with sour has ion receptors for transduction of signals. Function, guides consumption of NaCl and are involved in ion and water homeostasis.

Question 6

What 3 types of taste cells are found in a taste bud?

Answer 6

Type 1: Support cells
Type 2: Receptor cells (Mature in center, immature on the peripheral)
Type 3: Release neurotransmitters at the surface

Question 7

What cells are responsible for the constant renewal cycle of taste receptor cells in taste buds?

Answer 7

Basal Cells

Question 8

A tastant (soluble chemical) diffuses through the pore of the taste bud and interacts with the taste receptor proteins on microvilli of taste receptor cells. From there taste is detected when what happens?

Answer 8

Taste is detected when Neurotransmitters are released by a taste receptor cell at the synapse with a nerve terminal of sensory ganglia at the base of the cell.