Peripheral/Autonomic Nervous System Flashcards
How many roots does the spinal cord have?
two roots
Which spinal cord root has predominantly motor function?
Ventral/front root –> motor function
Which spinal cord root has ganglion?
Dorsal/back root –> ganglion
What is the function of spinal nerves?
Are spinal nerves mixed?
Yes, they’re mixed (sensory and motor)
Sensory -> Sends signals to the brain via dorsal root
Motor –> Sends signals from brain to spinal cord via ventral root
What is the name of the bundles that arranges axons?
Fasciculus
What are the 3 layers of the connective tissue wraps of the axon?
- Endoneurium
- Perineurium
- Epineurium
What are dermatomes?
Areas of the skin that connect thru a single spinal nerve
What are dermatomes used for?
Used to diagnose spinal cord injuries
What are the two rami of the spinal nerves?
- Dorsal ramus
- ventral ramus
What is the third additional ramus of the spinal nerves b/w T1-L2?
Communicating ramus
How many spinal nerves are in humans?
62 spinal nerves
What does the dorsi rami/ramus do?
Innervates the vertebral muscles
What is the origin of the phrenic nerve?
Formed from C3-C5
What muscle does the phrenic nerve innervate?
Innervates the diaphragm
What plexus is the phrenic nerve found in?
Cervical plexus
What is the role of the phrenic nerve in Hangman’s Fracture?
Damage to above the phrenic nerve makes it more difficult to breathing;
lacking of oxygen
Describe the nerve supply to the upper limb, and the group of muscles they innervate (5)
- Axillary nerve innervates deltoid
- Radial nerve innervates triceps
- Musculocutaneous nerve innervates biceps brachii
- Median nerve innervates flexors like the flexor carpi radialis
- Ulnar nerve innervates flexor carpi ulnaris
Describe the nerve supply to the lower limb, and the group of muscles they innervate (4)
- Femoral nerve innervates quadriceps/ helps with knee movement
- Obturator nerve innervates inner thigh muscles
- Sciatic nerve innervates posterior thigh muscles like hamstring
- Gluteal nerve innervates gluteal muscles
How many cranial nerves are in humans?
12 cranial nerves
What nerve in the cervical plexus?
phrenic nerve