Sensory receptors and the somatic nervous system

Question 1

Role of peripheral nervous system

Answer 1

Relay sensory information from the periphery and internal environment into the CNS via afferent pathways.

Relay motor output from the CNS to the skeletal
and smooth muscles via efferent pathways.

Question 2

Somatic senses

Answer 2

Touch
Temperature
Pain
Proprioception

Question 3

Special senses

Answer 3

Smell
Taste
Hearing
Balance
Vision

Question 4

Visceral senses

Answer 4

Blood pressure
Distension of GI tract
Internal body temperature
Blood glucose concentration
Internal pH

Question 5

Common sensory pathway

Answer 5

Stimulus
Sensory receptor
Signal transduction
Sensory neurone
Integration centre CNS
leads to:
Brain = conscious perception
OR
Spinal cord = unconscious perception
Motor neurone
Skeletal muscle

Question 6

Somatic sensory receptors

Answer 6

Modified or free nerve endings of sensory neurons

Question 7

Special sense receptors

Answer 7

Receptor cells that synapses with sensory neurone

Question 8

Mechanoreceptors location

Answer 8

Mostly skin

Question 9

Mechanoreceptors stimuli

Answer 9

Physical distortion (touch)

Question 10

Mechanoreceptors subtypes

Answer 10

Meissners corpuscles: glabrous, low threshold touch
Merkels disk: glabrous, low threshold static touch
Ruffinis corpuscles: glabrous and hairy, high threshold stretch
Pacinian corpuscles: largest, deepest, vibration
Free nerve endings: glabrous and hairy, very high touch threshold

Question 11

Thermoreceptors location

Answer 11

Mostly skin

Question 12

Thermoreceptors stimuli

Answer 12

Temperature

Question 13

Thermoreceptors free nerve endings ion channels

Answer 13

TRPV1: hot
TRPM8: cold

Question 14

Nociceptors location

Answer 14

Mostly skin

Question 15

Nociceptors stimuli

Answer 15

Stimuli that have potential to cause tissue damage

Question 16

Nociceptors free nerve endings

Answer 16

Mechanical nociceptors
Thermal nociceptors
Chemical nociceptors

Question 17

Proprioceptors location

Answer 17

Muscles, tendons, ligaments, joints

Question 18

Proprioceptors stimuli

Answer 18

Muscle tension

Question 19

Proprioceptors subtypes

Answer 19

Muscle spindles: AKA stretch receptors, muscle length
Golgi tendon organ: Muscle tension (force of contraction)
Proprioceptors in joints: Angle, direction and velocity of movement in a joint

Question 20

Sensory transduction

Answer 20

Converting stimulus energy into electrical signals.
Activation of receptor causes the movement of ions = change in the membrane potential
Receptor = receptor potential
Sensory neurone = Action potential

Question 21

Receptive fields

Answer 21

Area in which the specific stimulus will activate the sensory receptor.
High density of smaller receptive fields = higher spatial resolution of the stimulus
Fingers and lips = highly discrimitive