Special senses

Question 1

What is taste also called?

Smell?

Answer 1

Gustation

olfaction

Question 2

The receptors for olfaction and gustation are called what?

Answer 2

chemoreceptors

Question 3

What must occur to both odorants and tastants to be detected?

Answer 3

Odorants - dissolved in mucus

tastants - dissolved in saliva

Question 4

Where are the taste buds located?

What do they contain?

Answer 4

Mucosa of mouth and pharynx
most on surface of tongue
contain taste receptor cells and basal cells

Question 5

What is the mucosa of the mouth and pharynx?

Answer 5

stratified squamous, non-keratinized

Question 6

Other than cells, what else do tastes buds have?

Answer 6

long microvilli called gustatory hairs

- bathed in saliva and contain dissolved molecules that stimulate taste

Question 7

Cells in the taste buds are ______ replaced every _ - _ days.

Answer 7

constantly

7-10

Question 8

How can gustatory hairs be activated?

Answer 8

Molecules in food need to be dissolved in saliva.

Question 9

What do basal cells do?

Answer 9

Divide to replace worn out gustatory cells.

Question 10

How many salivary glands do we have?

What do they make?

Answer 10

3

saliva and mucus

Question 11

What are the five basic qualities of taste?

Answer 11

Bitter, sweet, salty, sour, umami

Question 12

What is umami elicited by?

Answer 12

glutamate

Question 13

Why is the taste map a myth?

Answer 13

All tasted modalities can be elicited from all areas containing taste buds.

Question 14

Chemicals that stimulate gustatory receptors are called ______.

Answer 14

tastants

Question 15

Describe the gustatory pathway.

Answer 15

Tastants dissolved in saliva
make contact with gustatory hairs which stimulate sensory neurons
Impulses reach thalamus which relays it to gustatory area in the insula - conscious perception of taste; and also to the limbic system - emotional response

Question 16

Olfaction:

Olfactory receptors are part of the _______ epithelium on the _____ of the nasal cavity

Answer 16

olfactory

roof

Question 17

What does sniffing do?

Answer 17

draws in more air and intensifies sense of smell

Question 18

What is the epithelium of the nasal mucosa?

What cells does it contain?

Answer 18

Pseudostratified ciliated columnar epithelium
1 - Olfactory receptors cells
2 - supporting epithelial cells
3 - Basal epithelial cells
4 - Olfactory glands

Question 19

What do supporting epithelial cells do?

Answer 19

provide support and nourishment

Question 20

What do basal epithelial cells do?

Answer 20

can form new receptors monthly

Question 21

What do olfactory glands do?

Answer 21

secrete mucus

Question 22

How is the function of basal epithelial cells unique to the body?

Answer 22

Regenerates neurons

Question 23

What is a difference between the receptors of gustation and olfaction?

Answer 23

Receptor in olfaction are actual neurons

receptor in gustation are simple squamous epithelial cells

Question 24

Olfactory sensory receptors:

• cell bodies located in _______ epithelium
• • have an apical ______ that projects to the epithelial surface
• • ends in a knob from which olfactory ____ radiate
• –olfactory ____ act as receptive structures for smell by binding to ______
• -Epithelium also covered with _____ which captures and dissolves odour molecules

Answer 24

olfactory
- apical - dendrite
- ends in knob - olfactory cilia radiate from here
cilia
mucus

Question 25

Describe the olfactory pathway.

Answer 25

odorant dissolved in mucus
- binds to and activates olfactory cilia
– axons of olfactory receptors gather in bundles to form the olfactory nerve
— olfactory nerve passes through the ethmoid bone, enters the olfactory bulb and synapses with mitral cells
—- mitral cells transmit impulses along the olfactory tract to:
1 - limbic system - emotion
2 - piriform lobe/olfactory cortex - conscious perception of odour

Question 26

The olfactory neuron is ______.

Answer 26

bipolar

Question 27

What is anosmia?

Answer 27

absence of sense of smell

- can be due to injury, zinc deficiency, colds/allergies and polyps