16.1

Question 1

What is the conscious or subconscious awareness of changes in the external and internal environment ?

Answer 1

Sensation

Question 2

What is the interpretation of sensations and is primarily a function of the cerebral cortex?

Answer 2

Perception

Question 3

What is the uniqueness of each sensation; distinguishes one sensation from another (touch, pain, vision, hearing) called?

Answer 3

Sensory modality

each sensory neuron only carries one modality

Question 4

What are the 2 classes of sensory of sensory modalities?

Answer 4

1. GENERAL SENSES
2. SPECIAL SENSES

Question 5

What are the 2 types of general senses?

Answer 5

1. Somatic senses
2. Visceral senses

Question 6

Which type of sense is this?
Tactile sensations (touch, pressure, vibration, itch, tickle)
Thermal sensation (heat or cold)
Pain sensations
Proprioreceptive receptors
Movements of limbs and head
Positions of limbs and body parts

Answer 6

Somatic senses
(Type of general senses)

Question 7

What are visceral senses?

Answer 7

Provide information about conditions within internal organs (pressure, stretch, chemicals, nausea, hunger)

Question 8

What are special senses?

Answer 8

Sensory modalities of smell, taste, vision, hearing, equilibrium or balance

Question 9

Where does the process of sensation begin in?

Answer 9

A sensory receptor (can be either a specialized cell or the dendrites of a sensory neuron)

Question 10

When does a sensory receptor respond?

Answer 10

Vigorously to a stimulus (change in environment)
Weakly or not at all to all other stimuli

Question 11

What are free nerve endings?

Answer 11

Bare, not encapsulated dendrites
Lack any structural specializations that can be seen under a light microscope

Question 12

What are encapsulated nerve endings?

Answer 12

Their dendrites are enclosed in a connective tissue capsule that has a distinctive microscopic structure (ex. Lamellated corpuscles)

Question 13

What do the different types of capsules enhance in encapsulated nerve endings?

Answer 13

Enhance the sensitivity or specificity of the receptor

Question 14

What type of nerve endings would receptors for pain, temperature, tickle, itch and some touch sensations? (Free nerve endings or encapsulated nerve endings)

Answer 14

Free nerve endings

Question 15

What types of receptors would be encapsulated nerve endings? (Examples)

Answer 15

Receptors for other somatic and visceral sensations (such as pressure, vibration and some touch sensations)

Question 16

What are seperate cells ?

Answer 16

Sensory receptors for some special senses are specialized special cells that synapse with sensory neurons

Question 17

What are some examples of separate cells?

Answer 17

Hair cells for hearing and equilibrium in the inner ear, gustatory records for taste buds & photoreceptors in the retina of the eye for vision

Question 18

Are olfactory receptors for the sense of smell separate cells?

Answer 18

No
They are located in olfactory cilia
(Hair like structures that project from the dendrite of an olfactory receptor cell)

Question 19

A sensory experience that receptor responds to a stimulus be creating a graded potential called?

Answer 19

Receptor potential

Question 20

In sensory receptors with free nerve endings or encapsulated nerve endings, how do the nerve impulses reach the CNS?

Answer 20

If the receptor potential is large enough to reach threshold it triggers one or more nerve impulses in the axon of the sensory neuron
The nerve impulses propagate along the axon into the CNS

Question 21

In seperate cells, how do the nerve impulses reach the CNS?

Answer 21

The receptor potential triggers the release of a neurotransmitter through exocytosis of synaptic vesicles.
The neurotransmitters liberated from the synaptic vesicles diffuse across the synaptic cleft and produce a postsynaptic potential
If the threshold is reached the PSP will trigger one or more nerve impulses which propagate along the axon to the CNS

Question 22

Receptors located at or near the external surface of the body; are senstive to stimuli originated outside the body & provide info about the external environment ?

Answer 22

Exteroreceptors

Question 23

Which receptors would be involved with the sensation of hearing, vision, smell, taste, touch, pressure, vibration, temperature & pain

Answer 23

Exteroreceptors

Question 24

What are interoreceptors? (Or visceroreceptors)

Answer 24

Located in the blood vessels, visceral organs, muscles and nervous system and monitor conditions in the internal environment. Nerve impulses produced by interoreceptors usually not consciously perceived - activation of strong stimuli may be felt as pain or pressure

Question 25

Which receptors are located in the muscles, tendons, joints and inner ear. They provide information about body position, muscle length, tension and the position and movement of joints?

Answer 25

Proprioceptors

Question 26

Which receptors are sensitive to mechanical stimuli such as the deformation, stretching or bending of cells. They provide sensations of touch, pressure, vibration, proprioception, heating & equilibrium and also monitor the stretching of blood vessels & internal organs?

Answer 26

Mechanoreceptors

Question 27

What do thermoreceptors do?

Answer 27

Detect change in temperature

Question 28

Which receptors respond to painful stimuli resulting from physical or chemical damage to tissue?

Answer 28

Nociceptors

Question 29

What do chemoreceptors do?

Answer 29

Detect chemicals in the mouth (taste), nose (smell) and body fluids

Question 30

What do osmorecptors do?

Answer 30

Detect the osmotic pressure of body fluids

Question 31

A characteristic of most sensory receptors is adaptation. What does this mean?

Answer 31

The receptor potential decreases in amplitude during a maintained, constant stimulus.
This causes the frequent of nerve impulses in the sensory neuron to decrease.
The perception of a sensation may fade or disappear even though the stimulus persists
Ex. Stepping into a hot shower

Question 32

Are receptors associated with vibration touch and smell rapidly adapting or slowly adapting receptors ?

Answer 32

Rapidly adapting receptors