Peripheral Nervous System

Question 1

What are the two parts of the Peripheral Nervous System?

Answer 1

Somatic (controls voluntary responses)
Autonomic (controls involuntary responses)

Question 2

Somatic system specs

Answer 2

Controls voluntary responses
Neurons service the head, trunk (mid of spine) & limbs
Sensory neurons carry info. about the environment inwards from receptors in the skin
Motor neurons will carry info. to the skeletal muscles
12 pairs of myelinated cranial nerves, for functions in the head, neck and face
EXCEPT
the Vagus Nerve, which connects to many internal organs (heart, lung, bronchi, digestive tract, liver & pancreas)
31 pairs of spinal nerves (all myelinated) containing sensory and motor neurons which service the area of the body where they are found

Question 3

Autonomic system specs

Answer 3

Controls involuntary responses (internal reactions to situations)
Nerves will either stimulate or inhibit the glands of the cardiac or smooth muscle (muscles not under voluntary control)
Maintains homeostasis by adjusting the body to variations in the external & internal environment
Controlled by the hypothalamus & Medulla (Oblongata)

Question 4

Sympathetic Nervous System specs

Answer 4

Activated under stressful situations
“Fight or flight”
Releases norepinephrine (excitatory, muscles contract)
Triggers adrenal glands to release epinephrine and norepinephrine (hormones) to activate the stress response
Inhibits digestive functions and bladder sphincters (use energy)

Question 5

Parasympathetic Nervous System specs

Answer 5

Activated when the body is calm and at rest
Restored and conserves energy -> “rest and digest”
Slows heart rate, breathing rate, reduced blood,pressure, promotes digestion, stimulates reproductive organs