Foundation 6.5: Taste (Gustation) & Smell (Olfaction)

Pheromones

Chemical signal released by a member of a species that is sensed by another member of the species and triggers an innate response; humans rely very little on this

Olfactory epithelium

Tissue in the nasal cavity that detects odor molecules

Olfactory bulb

Brain structure that receives information from the olfactory epithelium

Accessory olfactory bulb

Structure that receives input from accessory olfactory epithelium; absent in humans

Mitral cell

Neuron in the olfactory bulb that relays smell signals to other brain areas

Olfaction

Sense of smell

Gustation

Sense of taste

Taste bud

Cluster of taste receptor cells on the tongue

Bitter

Taste associated with potentially toxic substances

Salty

Taste associated with sodium ions

Sweet

Taste associated with sugars and energy-rich nutrients

Sour

Taste associated with acidic compounds

Umami

Taste associated with amino acids like glutamate

Cribriform plate

Bone with small holes through which olfactory nerve fibers pass

Olfactory nerve

Nerve that transmits smell information from the nose to the brain

Olfactory receptor

Sensory receptor that detects odor molecules

Glomerulus

Structure in the olfactory bulb where olfactory receptor neurons converge

Papillae

Structures on the tongue that contain taste buds

Fungiform papillae

Mushroom-shaped papillae on the front of the tongue containing taste buds

Foliate papillae

Fold-shaped papillae on the sides of the tongue with taste buds

Circumvallate papillae

Large dome-shaped papillae at the back of the tongue containing many taste buds

Labelled line model

Theory that each taste receptor cell connects to the brain via a separate pathway

Epithelial cells

Cells that line the surfaces of the body including the tongue and nasal cavity