What are the 12 Cranial Nerves in order?
- Olfactory - Used for scent
- Optic - Contains that optic nerve & chiasma
- Oculomotor - Used for eye movement, posterior to the optic chiasma
- Trochlear - Enters the superior aspect of the eye
- Trigeminal - Facial & Jaw nerves, has 3 brances
- Abducens - Used for eye movement
- Facial - Large clusters of nerves that run into the face
- Vestibulocochlear - Used for balance & hearing, posterior to facial nerves
- Glossopharyngeal - Runs into the tongue & pharynx
- Vagus - Runs inferior to the thoracic cavity to regulate the heart, lungs, digestive, etc.
- Accessory - Runs to neck & back muscles
- Hypoglossal - Runs under the tongue, used for swallowing & speech
What are the three meninges (layers of tissue) surrounding the spinal cord?
Dura mater - Outermost double-layer membrane
Arachnoid mater - Web-like middle layer
Pia mater - Innermost layer, touches the brain & spinal cord
When a nerve splits as it enters the spinal foramen, what does it split into?
Dorsal Root - bulbous, thicker root; the most posterior of the two
Ventral Root - thinner root; the most anterior of the two branches
What are the 5 components of a Reflex Arc?
- The receptor is the site of stimulus action
- The sensory neuron transmits an afferent impulse to the Central Nervous System (CNS)
- The integration center consists of one or more neurons in the CNS
- Motor Neuron
- Effector
What are the three Auditory Ossicles (Ear Bones)?
Malleus - The “hammer”
Incus - The “anvil”
Stapes - The “stirrup” inferior to the incus
Where does the phrenic nerve originate?
Where does it innervate?
Origin: C3 - C5 Nerve Roots of the Cervical Plexus
Innervates the diaphragm
Where does the axillary nerve originate?
Where does it innervate?
Origin: C5 & C6 Nerve Roots of the Brachial Plexus
Innervates the deltoid & teres minor as well as some skin of the shoulder region
Where does the femoral nerve originate?
Where does it innervate?
Origin: L2 - L4 Nerve Roots of the Lumbar Plexus
Innervates the skin of the anterior and medial thigh, skin of the foot, hip, & knee joints, anterior motor muscles (quadriceps & sartorius), the pectineus, & the iliacus
Where does the obturator nerve originate?
Where does it innervate?
Origin: L2 - L4 Nerve Roots of the Lumbar Plexus
Innervates the adductor magnus, longus, & brevis muscles, the gracilis, and the skin of the medial thigh
Where does the sciatic nerve originate?
Where does it innervate?
Origin: L4 - S3 Nerve Roots of the Sacral Plexus
Innervates the skin of the lower leg. The sciatic nerve branches proximal to the knee, creating the Tibial and Common Fibular Nerves
