Physiology of Taste

Physiology of Taste

Taste Buds - Papillae

Taste is the sensation that occurs in the mouth when a substance reacts chemically with taste receptor cells located on _____ ____ or ________.

Pores

Testant (in sol. form) enters _____ of taste buds.

Microvilli

Testants in taste buds reacts with receptor molecule on?

Taste Buds

Small structures found mostly on the tongue.

50-100 Cells

Each taste buds contain about how many cells (range).

Microvilli

Taste buds have __________ that project into a small opening called the taste pore, where they contact dissolved food molecules.

Taste Receptor Cells (Gustatory Cells)

Are specialized epithelial cells inside the taste buds that act as the actual sensory receptors for taste.

Ion Channels

Specialized protein molecules found in cell membranes that allow ions to pass in and out of the cell.

Ion Channels

They function like "gates or pores" that open and close in response to specific signals, helping control the cell's electrical activity, signaling, and homeostasis.

Signaling Cascade

Acts as second messenger pathway.

Signaling Cascade

Activates G protein (Gustducin) triggers a chain of intracellular signaling molecules.

Signaling Cascade

These signals cause ion channels in the cell to open, leading to depolarization.

Neurotransmitters

Depolarization of receptor cells leads to the release of?

Neurotransmitters

These activate Sensory Neuron or afferent nerve fibers that carry the signal to the brain.

Facial nerve (CN VII) - Glossopharyngeal nerve (CN IX) - Vagus nerve (CN X)

Cranial nerves involved in neural pathways (3).

Nucleus of the Solitary tract (NST)

All fibers project to the Nucleus of this tract in the medulla.

Nucleus of the Solitary tract (NST)

The first relay station in the brain for taste.

Thalamus - Primary Gustatory Cortex

From the NST → signals are relayed to the ________. Then projected to the _______ _________ ______ (Insula and frontal operculum).

Gustatory Cortex (Insula and Frontal Operculum)

The primary brain area responsible for taste perception.