AP Exam 5

Ch 11 (partial) & Ch 12

What are the 3 functions of the meninges?

To secure, cushion, and organize the brain & spinal cord.

What type of tissue makes up the meninges?

Connective tissue

What are the 3 layers of the meninges?

Dura mater, arachnoid mater, and pia mater

What potential space within the skull is fatal if a hematoma develops?

Epidural space (develops quickly, will cause death)

What does the cranial epidural space contain VS the spinal epidural space?

brain: blood vessels (epidural hematoma may form) spinal cord: fat, vessels (location of analgesia)

What does the cranial dura mater layer contain vs the spinal dura mater layer?

Brain: 2 layers (periosteal/meningeal), forms venous sinuses for blood return through the circulatory system, separates brain structures. Spinal dura mater: PS

What does the subdural space contain?

Filled with serous fluid and vessels. (Can get a subdural hematoma, bleeds slower)

What is the dura mater made of?

Strong-collagen, some elastic.

What is the arachnoid mater made of?

A web-like structure made of dense irregular connective tissue.

What does the cranial arachnoid mater contain vs the spinal arachnoid mater?

Brain: arachnoid granulation, which drains the cerebral fluid. Spinal: lumbar puncture to obtain CSF for testing.

Which space in the meninges contains the cerebral spinal fluid?

subarachnoid space

What does the pia mater contain?

Spinal pia mater contains denticulate ligaments which stabilizes the spinal cord. It follows the contours of the brain/spinal cord.

What part of the brain produces CSF?

Choroid plexus with ependymal cells.

What are the functions of CSF?

Cushions the brain/spinal cord, removes waste, and increases buoyancy of the brain.

How many mL of CSF is made a day, and how often is it replaced?

About 800mL/day, completely replaced about 5-6x per day.

What type of information does the posterior gray horn receive?

Sensory information only! (afferent)

What type of information does the anterior gray horn receive?

Somatic motor information only! Skeletal muscle (efferent)

What type of information does the anterior white column/ventral root receive?

Motor information only!

What type of information does the lateral white column/gray horn receive?

Autonomic (cardiac muscle, glands etc)

What is the main function of the parasympathetic nervous system?

Maintenance of homeostasis while you’re at rest.

What is the main function of the sympathetic nervous system?

Maintenance while doing physical work, visceral response to emotion.

Is sensory information voluntary or involuntary?

involuntary

How many pairs of spinal nerves are there?

31

How many cervical nerves are there vs cervical vertebrae?

7 cervical vertebrae, and 8 cervical nerves.

What are the four major nerve plexuses?

cervical, brachial, lumbar and sacral.

Define dermatomes

specific areas of skin supplied by sensory fibers from a single spinal nerve root

What is the outer layer of a fascicle?

Epineurium

What is the middle layer of a fascicle?

Perineurium

What is the inner layer of a fascicle?

Endoneurium

What is cranial nerve 1?

olfactory nerve (S)

What is cranial nerve 2?

Optic (S)

What is cranial nerve 3?

oculomotor (M)

What is cranial nerve 4?

Trochlear (M)

What is cranial nerve 5?

Trigeminal (B)

What is cranial nerve 6?

Abducens (M)

What is cranial nerve 7?

Facial (B)

What is cranial nerve 8?

Vestibulocochlear (S)

What is cranial nerve 9?

Glossopharyngeal (B)

what is cranial nerve 10?

Vagus (B)

what is cranial nerve 11?

Accessory (M)

What is cranial nerve 12?

hypoglossal (M)