Ch. 13 Peripheral Nervous System

Question 1

Peripheral nerves & ganglia consist of

Answer 1

Afferent nerves and Efferent Nerves

Question 2

Sensory receptors respond to…

Answer 2

Change in their environment called stimuli

Stimulus initiates graded potential (local depolarization) that then in turn triggers nerve impulses along afferent PNS fibers to the CNS

Question 3

Classification by stimulus type

Mechanoreceptors: 
Thermoreceptors:
Photoreceptors:
Chemoreceptors:
Nociceptors:

Answer 3

Mechanoreceptors: mechanical force, touch and pressure
Thermoreceptors: Temperature changes
Photoreceptors: Light energy
Chemoreceptors: chemicals in solution
Nociceptors: potentially damaging stimuli that result in pain

Question 4

Classification by location:

Answer 4

Exteroceptors: Superficial (skin). Respond to stimuli arising outside the body. Include receptors for touch, pressure, pain, vibration, temperature, limb motion, and special senses (vision, hearing, equilibrium, taste, smell)

Interoceptors (Visceroceptors): Internal respond to stimuli arising within body such as internal viscera and blood vessels. Include receptors for stretch, pain, temperature, chemical, changes (nausea, hunger, etc)

Propioceptors: Respond to internal stimuli like above , but locations is restricted to skeletal muscles, tendons, joints, and ligaments.
Constantly advise brain on body movements.

Question 5

Classification by Structural Complexity:

Answer 5

Simple:
Modified dendritic endings of sensory neurons.
Located throughout body and monitor general sensory info, (touch, stretch, temp, pressure, chemicals, etc.)

Complex:
Clusters of multiple cell types; usually considered sense organs.
Associated with special senses: vision, hearing, equilibrium, smell, and taste.

Question 6

Structure of a Nerve

Connective Tissue Wrappings

Answer 6

En