A&P I Laboratory #12: Spinal Cord and Nerves

Flashcards on the spinal cord anatomy, nerves, and cranial nerves as discussed in Dr. Benitez's lecture.

Cervical enlargement

A region of the spinal cord that supplies nerves to the upper limbs.

Lumbar enlargement

A part of the spinal cord that supplies nerves to the lower limbs.

Conus medullaris

The tapered end of the spinal cord.

Cauda equina

A bundle of spinal nerves and spinal nerve roots located in the lower back.

Filum terminale

A fibrous extension of the conus medullaris that anchors the spinal cord to the coccyx.

Dura mater

The outermost layer of the meninges surrounding the brain and spinal cord.

Denticulate ligament

The fibrous structure that anchors the spinal cord to the dura mater.

Subdural space

The potential space between the dura mater and the arachnoid mater.

Arachnoid mater

The middle layer of the meninges that resembles a web.

Subarachnoid space

The space between the arachnoid mater and pia mater, containing cerebrospinal fluid.

Pia mater

The delicate innermost layer of the meninges that clings to the surface of the brain and spinal cord.

Anterior median fissure

A deep groove that divides the spinal cord into left and right halves.

Posterior median sulcus

A shallow groove on the posterior side of the spinal cord.

White matter

Myelinated axons in the spinal cord responsible for transmitting signals.

Gray matter

Cell bodies and unmyelinated axons in the spinal cord, organized into horns.

Anterior horns

Regions of gray matter in the spinal cord that contain motor neurons.

Posterior horns

Regions of gray matter in the spinal cord that contain sensory neurons.

Lateral horns

Regions of gray matter located in the thoracic and upper lumbar regions of the spinal cord.

Central canal

A small channel located in the center of the spinal cord, filled with cerebrospinal fluid.

Anterior root

The root of a spinal nerve that contains motor fibers.

Posterior root

The root of a spinal nerve that contains sensory fibers.

Dorsal root ganglion

A cluster of sensory neuron cell bodies located in the posterior root.

Cormus communicans

A small nerve that connects the spinal nerve with the sympathetic chain.

Phrenic nerve

A nerve arising from the cervical plexus that controls the diaphragm.

Brachial plexus

A network of nerves that supplies the upper limb.

Axillary nerve

A nerve of the brachial plexus that innervates the shoulder muscles.

Musculocutaneous nerve

A nerve that supplies the coracobrachialis, biceps brachii, and brachialis.

Ulnar nerve

A nerve that innervates the forearm and hand.

Median nerve

A nerve that supplies the majority of flexor muscles in the forearm.

Radial nerve

A nerve that innervates the posterior compartment of the arm and forearm.

Lumbar plexus

A network of nerves that supplies the lower abdomen and parts of the lower limb.

Femoral nerve

A nerve that provides motor and sensory function to the thigh.

Sacral plexus

A network of nerves that supply the pelvic region and lower limbs.

Sciatic nerve

The largest nerve in the body, innervating the lower limb.

Axons

The long, slender projections of neurons that conduct electrical impulses.

Schwann cells

Supporting cells in the peripheral nervous system that form myelin sheaths.

Fascicle

A bundle of axons in a nerve.

Endoneurium

The connective tissue wrapping around individual axons.

Perineurium

The connective tissue that surrounds a fascicle.

Epineurium

The outermost layer of connective tissue surrounding a nerve.

Cranial nerves

Nerves that emerge directly from the brain.

Olfactory nerve (CN I)

A sensory nerve responsible for smell.

Optic nerve (CN II)

A sensory nerve responsible for vision.

Oculomotor nerve (CN III)

A motor nerve that controls most of the eye's movements.

Trochlear nerve (CN IV)

A motor nerve that controls the superior oblique muscle of the eye.

Trigeminal nerve (CN V)

A mixed nerve responsible for sensation in the face and motor functions such as biting and chewing.

Abducens nerve (CN VI)

A motor nerve that controls lateral movement of the eye.

Facial nerve (CN VII)

A mixed nerve responsible for facial expressions and taste.

Vestibulocochlear nerve (CN VIII)

A sensory nerve responsible for hearing and balance.

Glossopharyngeal nerve (CN IX)

A mixed nerve responsible for taste and some functions of the pharynx.

Vagus nerve (CN X)

A mixed nerve that innervates internal organs.

Accessory nerve (CN XI)

A motor nerve that controls the shoulder and neck muscles.

Hypoglossal nerve (CN XII)

A motor nerve that controls tongue movements.