Spinal Cord Anatomy and Reflexes

These flashcards cover essential topics related to the anatomy of the spinal cord, spinal nerves, reflexes, and associated structures.

What is the primary function of the spinal cord?

The spinal cord serves as a vital link between the brain and the rest of the body.

What are the two main functions of spinal nerves?

1. They provide a pathway for sensory and motor impulses. 2. They are responsible for reflexes.

What is the average length of the spinal cord?

The spinal cord is typically 16-18 inches long.

What are the five regions of the spinal cord?

Cervical, Thoracic, Lumbar, Sacral, and Coccygeal.

What is the conus medullaris?

The conus medullaris is the tapering inferior end of the spinal cord.

What does the term cauda equina refer to?

The cauda equina refers to the collection of nerve roots extending inferiorly from the conus medullaris.

What is the function of the filum terminale?

The filum terminale is a thin strand of pia mater that anchors the conus medullaris to the coccyx.

How many pairs of spinal nerves are associated with the spinal cord?

There are 31 pairs of spinal nerves.

What are the three layers of spinal meninges?

Dura mater, arachnoid mater, and pia mater.

What is found in the subarachnoid space?

The subarachnoid space is filled with cerebrospinal fluid (CSF).

What shape does gray matter take in the spinal cord cross-section?

Gray matter in the spinal cord resembles a butterfly or an 'H' shape.

What is the difference between monosynaptic and polysynaptic reflexes?

Monosynaptic reflexes involve one synapse between sensory and motor neurons, while polysynaptic reflexes involve multiple synapses with interneurons.

What is a reflex arc?

A reflex arc is the neural wiring of a reflex that includes a sensory receptor, sensory neuron, interneurons, motor neuron, and an effector.

Give an example of a spinal reflex.

The withdrawal reflex is a common spinal reflex that occurs in response to painful stimuli.

What is a dermatome?

A dermatome is a segment of skin supplied by a single spinal nerve.

What are nerve plexuses?

Nerve plexuses are networks of interweaving anterior rami of spinal nerves that split into multiple named nerves.

What is the major nerve of the brachial plexus?

The brachial plexus major terminal branches include the axillary, musculocutaneous, median, radial, and ulnar nerves.

What structure does the lumbar plexus mainly innervate?

The lumbar plexus primarily innervates the lower limbs.

What are the main nervous structures originating from the sacral plexus?

The main branches include the tibial nerve and common fibular nerve.

What is the role of the Golgi tendon reflex?

The Golgi tendon reflex inhibits muscle contraction to protect the muscle and tendon from excessive force.

What is the purpose of spinal reflexes?

Spinal reflexes provide quick, automatic responses to stimuli.