Chapter 15: Special Senses and Smell

Question 1

What are the five special senses

Answer 1

smell

taste

sight

balance

hearing

Question 2

olfaction

Answer 2

the physiological term for smell

Question 3

olfactory epithelium

Answer 3

the epithelial tissue that is made of ~10 million olfactory neurons.

dendrites of olfactory neurons have enlarged “olfactory vesicles”

Question 4

olfactory hairs

Answer 4

cilia of olfactory neurons found in the mucus. They pick up “odorants” or molecules of smell.

Question 5

odorants

Answer 5

this dissolve in the mucus and then attach to the receptors, causing a depolarization of the molecule and that signal gets sent back to the olfactory nerve.

Question 6

how is the epithelial tissue of the olfactory epithelium different from the other special senses

Answer 6

it is replaced quite often because it is exposed to the outside. They are replaced by basal cells

Question 7

what is the pathway for olfaction?

Answer 7

the olfactory neurons are bipolar, so when they pick up an odarant, the molecule binds to the receptor causing which sends the signal through the cribiform plate to the olfactory bulbs and synapse with tufted cells or mitral cells. These extend to the olfactory tract and synapse with association neurons.

Question 8

how is the olfactory tract different than other systems

Answer 8

it bypasses the thalamus and goes straight to the olfactory cortex which is on the frontal lobe and is able to provide a direct shot to the brain, which is why it’s such an intense sensation.