Comprehensive Study Guide: Spinal Cord Anatomy, Reflex Arcs, and the Autonomic Nervous System

Flashcards identifying spinal cord structures, meningeal layers, reflex arc components, and autonomic nervous system ganglia and their targets.

Dura mater

The outermost layer of the spinal cord meninges.

Arachnoid mater

The middle layer of the meninges located between the dura mater and the pia mater.

Pia mater

The innermost layer of the meninges that closely adheres to the surface of the spinal cord.

Epidural space

The space located outside the dura mater.

Subdural space

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

Subarachnoid space

The space located between the arachnoid mater and the pia mater.

Denticulate ligament

Specialized extensions of the pia mater that help anchor the spinal cord.

Anterior/ventral root

The motor root of a spinal nerve.

Posterior/dorsal root

The sensory root of a spinal nerve.

Dorsal root ganglion

A cluster of nerve cell bodies in a posterior root of a spinal nerve.

Anterior median fissure

A wide, deep groove on the anterior surface of the spinal cord.

Posterior median sulcus

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

Central canal

A small hole in the center of the spinal cord that contains cerebrospinal fluid.

Spinal nerve

A mixed nerve formed by the union of the dorsal and ventral roots.

White mater

The portions of the spinal cord containing myelinated axons.

Gray mater

The portions of the spinal cord containing neuronal cell bodies and unmyelinated axons.

Cauda equina

A mass of nerves within the vertebral column.

Cauda equina (Latin translation)

Horse's tail

Conus medullaris

The cone-shaped tapered lower end of the spinal cord.

Intervertebral foramen

The opening between adjacent vertebrae through which spinal nerves exit.

Spinal (vertebral) foramen

The large opening in a vertebra that forms the vertebral canal housing the spinal cord.

Sensory receptor

The distal end of a sensory neuron that responds to a stimulus.

Sensory neuron

A nerve cell that conducts impulses from a receptor to the central nervous system; includes a cell body, axon, and dendrites.

Interneuron

A nerve cell within the spinal cord that relays signals between sensory and motor neurons; includes a cell body, axon, and dendrites.

Motor neuron

A nerve cell that conducts impulses from the central nervous system to an effector; includes a cell body, axon, and dendrites.

Effector

A muscle or gland that responds to motor nerve impulses.

Preganglionic efferent neuron

A neuron of the autonomic nervous system whose cell body is in the CNS and whose axon extends to an autonomic ganglion.

Postganglionic efferent neuron

A neuron of the autonomic nervous system whose cell body is in an autonomic ganglion and whose axon extends to an effector.

Celiac ganglion

An autonomic ganglion whose postganglionic neurons innervate the liver, stomach, and small intestine.

Superior mesenteric ganglion

An autonomic ganglion whose postganglionic neurons innervate the small intestine.

Inferior mesenteric ganglion

An autonomic ganglion whose postganglionic neurons innervate the large intestine, rectum, bladder, and genitals.

Vertebral autonomic ganglion/sympathetic chain

A series of linked ganglia located on either side of the vertebral column.