3.6

Question 1

Taste

Answer 1

Flavor chemicals stimulate receptors within the tastebuds of the tongue and oropharynx. Receptors depolarize neurons of:
- CN VII
- CN IX
- CN X

Question 2

Structure of the tongue: taste sensation

Answer 2

3 kinds of tase papillae each have taste receptors on the sides.
Each tase bud contains receptors that respond to a different flavor and is connected to its own neuron.

Question 3

Gustatory pathway

Answer 3

Cranial nerves carry flavor signals to the brainstem.
The pathway becomes bilateral to the thalami.
Thalamus to cerebral cortex.

Question 4

Where are olfactory cells located?

Answer 4

Nasal epithelium

Question 5

Olfactory transduction

Answer 5

Odorants bind the cilia of the olfactory cells.
Requires nasal mucous to trap odorant, and water droplet to carry it.
Olfactory fibers carry signal to become the olfactory nerve.
Receptors are odorant binding proteins on the cilia.
Chemosensitive = chemical exposure leads to depolarization
These receptors are on neurons
Regenerate; only live 1-2 months

Question 6

Central olfactory pathway

Answer 6

Olfactory signals are carried to
- limbic system
- reticular formation
- thalamus
- olfactory cortex

Question 7

Sacral sparing

Answer 7

Can help diagnose whether any signals are passing an injured area of the spinal cord
Assessed by examining the sensation and contraction of the external anal sphincter and the skin around the anus.