Principles of Anatomy and Physiology - Chapter 13: The Spinal Cord and Spinal Nerves

Vocabulary flashcards covering key terms and concepts from the lecture on the spinal cord and spinal nerves.

Spinal Cord

Part of the central nervous system (CNS) that is continuous with the brain.

Reflex

A quick, automatic response to certain stimuli involving the spinal cord and spinal nerves.

EPSPs

Excitatory postsynaptic potentials that increase the chance of a neuron firing.

IPSPs

Inhibitory postsynaptic potentials that decrease the chance of a neuron firing.

Gray Matter

Region of the spinal cord involved in summation of EPSPs and IPSPs.

White Matter

Region of the spinal cord containing motor and sensory tracts.

Meninges

Three protective connective tissue coverings of the brain and spinal cord.

Cerebrospinal Fluid

Fluid that provides shock absorption and is located in the subarachnoid space.

Conus Medullaris

The conical structure where the spinal cord terminates at the L1-L2 level.

Cauda Equina

Bundle of spinal nerves and rootlets that resemble a horse’s tail.

Plexus

Network of interweaving spinal nerves.

Dermatome

Segment of skin supplied by sensory fibers of a single spinal nerve.

Reflex Arc

Pathway through which a nerve impulse follows to produce a reflex.

Monosynaptic Reflex

Reflex arc with only one synapse.

Polysynaptic Reflex

Reflex arc with more than one synapse and more than two types of neurons.

Stretch Reflex

Causes contraction of a skeletal muscle in response to stretching.

Tendon Reflex

Causes relaxation of the muscle attached to a stimulated tendon.

Flexor (Withdrawal) Reflex

Withdrawal of a limb in response to injury or pain.

Crossed-Extensor Reflex

Maintains balance by extending the opposite limb during withdrawal.