Olfactory and Taste Hursh Patel Sharon Li
Do Now • Why do you think taste and smell work so closely together? • How many taste buds does an average human have? • What is a Tastant? • What is an odorant?
Taste and Smell: Why? • Taste and smell are closely involved with each other • Perception of chemicals in the air and in our food • Food “tastes” different when the sense of smell is damaged • It explains why food tastes differently when a person is sick.
The Mouth • Tastants are chemicals in food • Detected by taste buds • 5,000-10,000 taste buds • 1 taste bud contains 50-100 specialized sensory cells • located on the papillae • Distinguishes chemicals • Sweet, salty, sour, bitter, umami (savory)
How the mouth sends signals… • Signals are transferred to the ends of nerve fibers • Sends impulses along cranial nerves to taste regions in the brainstem • Impulses are relayed to the thalamus and onto Caudal Orbital cortex
Mouth Review • How does the mouth send signals?
The Nose • Odorants are airborne odor molecules • Mucus membrane is found at the roof of the nose • Contains sensory neurons through perforations (pores) through the bone • Cilia receive odorant stimuli at sensory neuron tips
How the nose sends signals… • Signaling begins at the roof of the nose • Signals are sent to olfactory bulbs • Then processed in Caudal Orbital cortex
Nose Review • How does the nose send signals?
Smell perception • The activity pattern of odorants acting on receptors are sent to the olfactory bulbs • Then it forms a spatial map to be able to recognize smells. • This information is sent to the primary olfactory cortex