Lecture 3: General Senses and Special Senses (Olfaction/ Taste)

Question 1

Where are sensory receptors located?

Answer 1

At the peripheral end of a sensory neuron.

Question 2

Simple Receptors

Answer 2

• free nerve endings
• myelinated or non-myelinated

example: nociceptors (pain receptors)

Question 3

complex receptors

Answer 3

-sensory endings are enclosed in specialized connective tissue.

ex: Pacinian corpuscle (sense touch)

Question 4

special sense receptors

Answer 4

• specialized nerve cells or receptor cells that release neurotransmitters onto sensory neurons at a synapse.

Question 5

the area monitored by a sensory receptors is called a

Answer 5

receptive field

Question 6

how does the size and density identify sensitivity?

Answer 6

Size and density identify how sensitive you are to stimulus in that region of the body.

Question 7

thermoreceptors

Answer 7

• sense temperature
• usually free ending in the dermis, skeletal muscles, liver, and hypothalamus

Question 8

chemoreceptors

Answer 8

-respond to water and lipid soluble substances that are dissolved in body fluids (blood, CSF)

Question 9

mechanoreceptors

Answer 9

• sensitive to stimuli that distort their plasma membranes (stretching, compression, twisting)

Question 10

what are the three types of mechanoreceptors?

Answer 10

1. Proprioceptors
2. Baroreceptors
3. Tactile receptors

Question 11

1. Proprioceptors

Answer 11

-monitors position of joints and muscles

-most structurally and functionally complex of general sensory receptors.

Question 12

2. Baroreceptors

Answer 12

-detect pressure change in walls of blood vessels and portions of digestive, respitory, and urinary tracts.

Question 13

3. Tactile receptors

Answer 13

• provide sensation of touch (shape or texture). pressure (degree and frequency of distortion) and vibration

Question 14

Photoreceptors

Answer 14

• respond to electromagnetic radiation (light)
• only found in human eye

Question 15

Nociceptors

Answer 15

• pain receptors
  with free nerve endings with large receptive fields and broad sensitivity.

Question 16

What are two types of axons that carry pain information?

Answer 16

Type A fibers

Type C fibers

Question 17

Type A Nociceptors

Answer 17

-myelinated
- carry sensation of fast or prickling pain (such as cut/injection)

Question 18

Type C Nociceptors

Answer 18

• unmyelinated
• carry sensation of slow, burning or aching pain (a bump or rug burn)

Question 19

How are receptors classified?

Answer 19

Based on how they respond.

Question 20

What are the two types of ways receptors are classified as?

Answer 20

1. Tonic
2. Phasic

Question 21

Tonic

Answer 21

-do not adapt
-always active, either increase or decrease action potentials stimuli change

Question 22

Phasic

Answer 22

• adapt
• inactive unless activated by stimuli

Question 23

How does phasic work?

Answer 23

Once stimulus reaches a steady state? it turns off.

2. this allows body to ignore information that has been evaluated and not found to be a threat to homeostasis (such as wearing clothes)

Question 24

Olfaction

Answer 24

sense of smell

Question 25

what happens when you inhale?

Answer 25

• when inhaling through nose, odorant chemicals are carried in the air that you breath.

-structures in nasal cavity including the nasal conchae (turinates) cause the airflow to become turbulent, directing some odorant chemicals to the paired olfactory orans located on the superior surface of the nasal cavity at the cribriform plate of the ethmoid bone.

Question 26

Olfactory organs are composed of two layers. Which two are they?

Answer 26

1. Olfactory Epithelium
2. Lamina propria

Question 27

1. Olfactory Epithelium consists of.

Answer 27

• Olfactory receptor cells
• supporting cells
• basal cells

Question 28

2. Lamina Propria consist of

Answer 28

• areolar (connective) tissue
• numerous blood vessels
• nerve fibers

Question 29

What does the lamina propria contain?

Answer 29

Olfactory glans which are secrete copious amount of mucus.

The mucus dissolves the airborne molecules