Olfaction

Olfaction

Olfaction

The sense of smell

Olfactory Organs

Organs located in the nasal cavity that provide the sense of smell, consisting of olfactory epithelium and lamina propria.

Olfactory Receptors

Highly modified sensory neurons or nerve cells responsible for detecting dissolved chemicals that interact with odorant-binding proteins.

Olfactory Pathways

A two-neuron pathway where olfactory cells respond to chemical signals, passing through the cribriform plate to synapse with neurons in the olfactory bulbs of the cerebrum.

Olfactory Cortex

The area where olfactory information is processed, directly receiving input from olfactory receptors without relaying through the thalamus.

Olfactory Glands

Glands that produce mucus to coat the surfaces of olfactory organs, allowing molecules to dissolve for detection.

Olfactory Discrimination

The ability to distinguish thousands of chemical stimuli based on patterns of receptor activity.

Olfactory Fatigue

Occurs when the response threshold to trigger a signal is too high due to repeated stimulation, leading to a temporary loss of sensitivity.

Odorants

Dissolved chemicals that stimulate olfactory receptors by interacting with odorant-binding proteins on the membrane surface.

Adenylyl Cyclase

An enzyme activated by the binding of an odorant to its receptor protein, converting ATP to cyclic AMP to trigger depolarization and initiate an action potential.

Olfactory Receptors

Receptors on the surface membranes of olfactory dendrites that interact with odorants to stimulate the sense of smell.

Odorants

Substances that stimulate olfactory receptors by interacting with odorant-binding proteins on the membrane surface.

Sodium Ion Channels

Channels in the plasma membrane that open in response to cAMP, leading to depolarization in olfactory sensory neurons.

Gustatory Epithelial Cells

Cells in the taste buds that respond to different taste stimuli and involve various receptor mechanisms.

G Protein-Coupled Receptors

Receptors that bind to sweet, bitter, and umami stimuli in taste buds, leading to depolarization and neurotransmitter release.