Peripheral Nervous System PNS

Question 1

Including nerves are bundles of axon

Ganglia are collections of cell bodies

Answer 1

■Cranial nerves has 12 pairs attached brain
Be sensory, motor, or mixed nerves.
Concerned with the head, neck and face
■ the spinal nerves
31 pairs attached to spinal cord
Al are mixed nerves.
Originate where two roots join on either side= dorsal inward and ventral outward.

Question 2

Divisions of the PNS / somatic system

Answer 2

Serves the skin, skeletal muscles and tendons
Most actions voluntary, but some due to reflexes: per programmed, built in circuits
That enable the body to react swiftly to stimuli
Require no conscious control
Reflex arc nerve pathway for a reflex لردود الفعليه ( kneecap) راس الركبه
Pupillary reflex حدقة العين

Question 3

Autonomc system
regulates the activity of cardiac muscle, smooth muscle, organs and glands.
Function automatically and involuntarily

Answer 3

Divisions of AS
Sympathetic Nervous System
● responsible for fight or flight response= increases heart rate = dilates bronchi= inhibits digestion.
● activities the adrenal gland to secrete: epinephrine and norepinephrine
● both increase blood pressure, causing the heart to beat stronger and faster.

Question 4

Parasympathetic NS
● responsible for the rest and digest response
. Decrease heart rate 
. Constricts bronchi
. Promotes digestion
● Nearotransmitter is a cetylcholine.

Answer 4

PNS