Module 20 - Special Senses: Smell

Question 1

What are the two categories senses are separated into? What differentiates them?

Answer 1

General senses: Receptors distributed over a large part of the body
Special senses: Receptors localized within specific organs.

Question 2

5 components making up special senses

Answer 2

smell
taste
sight
hearing
balance

Question 3

General senses are separated into 2 categories. What are they and what are their characteristics?

Answer 3

Somatic: Located in skin, muscles, joints
Visceral: Located in internal organs

Question 4

What makes up somatic senses? (5)

Answer 4

Touch
pressure
proprioception
temperature
pain

Question 5

What makes up visceral senses? (2)

Answer 5

pain
pressure

Question 6

What are the five types of receptors?

Answer 6

mechanoreceptors
chemoreceptors
thermoreceptors
photoreceptors
nociceptors

Question 7

What are mechanoreceptors?

Answer 7

compression, bending, stretching of cells: Touch, pressure, proprioception, hearing, and balance

Question 8

What are chemoreceptors?

Answer 8

chemicals become attached to receptors on their membranes: Smell and taste

Question 9

What are thermoreceptors?

Answer 9

respond to changes in temperature

Question 10

What are photoreceptors?

Answer 10

respond to light : vision

Question 11

What are nociceptors?

Answer 11

extreme mechanical, chemical, or thermal stimuli: Pain

Question 12

What does the hard palate do in the nasal cavity?

Answer 12

Separates nasal and oral cavities

Question 13

What does the cribriform plate of ethmoid bone do?

Answer 13

Its holes allow signals to move from nasal to cranial cavity.

Question 14

Function of ridges in nasal cavity?

Answer 14

Swirls air around to direct it towards the olfactory region.

Question 15

What kind of cells is the olfactory epithelium made of?

Answer 15

Epithelial cells, bipolar cells

Question 16

Where are chemoreceptors located in the olfactory epithelium? Relate location with function.

Answer 16

in olfactory hairs (cilia).
- surrounded by mucus
- odorants need mucus to dissolve them to activate receptors/depolarization

Question 17

7 classes of odors are

Answer 17

camphoraceous, musky, flora, pepperminty, ethereal, pungent, putrid

Question 18

Differentiate primary and secondary olfactory area

Answer 18

Primary olfactory area (olfactory cortex) – conscious perception of smell – frontal & temporal lobes
Secondary olfactory area – visceral and emotional reactions to smell (connected to habenula, near corpus collosum)

Question 19

Why does scent adaptation occur?

Answer 19

saturated receptors + synaptic inhibition

Question 20

What covers windpipe in gustation

Answer 20

epiglottis

Question 21

Give the 4 papillae

Answer 21

vallate papilla
foliate papilla
fungiform papilla
filiform papilla

Question 22

what is vallate papilla

Answer 22

v shaped, taste receptors in pockets
– V-shaped border between anterior and posterior tongue
– largest, least numerous: 8 to 12
– have taste buds

Question 23

what is foliate papilla

Answer 23

sides of tongue, leaf shape, degenerates the most with age
– sides of the tongue
– contain most sensitive taste buds; decrease in number with age.

Question 24

what is fungiform papilla

Answer 24

on surface of tongue
– irregularly scattered on superior surface of tongue
– have taste buds

Question 25

what is filiform papilla

Answer 25

shape like flame, no tastebuds, creates rough surface
– most abundant, superior surface of tongue
– no taste bud
– rough surface

Question 26

what in a taste bud sends the nervous system signals? which part is the location of chemoreceptors?

Answer 26

taste cells for NS
taste (gustatory) hair/microvilli for chemoreceptors

Question 27

why doesnt the taste (gustatory) cell have an axon?

Answer 27

its short, doesnt need one. releases neurotransmitters

Question 28

taste buds for … (5)

Answer 28

salt, sour, bitter, sweet, umami

Question 29

where does depolarization occur in gustatory cells

Answer 29

in gustatory hairs

Question 30

what are tastants? diff them and odorants

Answer 30

tastants dissolve in saliva (mucus for odorants). odorants are less specific than tastants.

Question 31

give the neuronal pathways for taste

Answer 31

facial, glossopharyngeal, vagus nerves