Chapter 13: The Spinal Cord, Spinal Nerves, and Spinal Reflexes

These flashcards cover key concepts related to the spinal cord, spinal nerves, and spinal reflexes, providing an effective study tool for reviewing important terms and definitions from Chapter 13.

What are the two main types of matter found in the spinal cord?

Gray matter and white matter.

What is the primary function of the spinal cord?

To carry sensory and motor information between the brain and the rest of the body.

How many regions are in the spinal cord and can you name them?

There are four regions: Cervical (C), Thoracic (T), Lumbar (L), and Sacral (S).

What does the central canal in the spinal cord contain?

Cerebrospinal fluid (CSF).

What are the cervical and lumbosacral enlargements responsible for?

Cervical enlargement supplies the shoulder and upper limb; lumbosacral enlargement supplies the pelvis and lower limb.

What is the conus medullaris?

The tapered, conical end of the spinal cord below the lumbar enlargement.

What do the anterior and posterior roots of a spinal nerve contain?

Anterior (ventral) root contains motor (efferent) neuron axons; posterior (dorsal) root contains sensory (afferent) neuron axons.

What is a dermatome?

A specific bilateral region of skin supplied by a single pair of spinal nerves.

What are the three connective tissue layers surrounding spinal nerves?

Epineurium (outermost), perineurium (middle), endoneurium (innermost).

What is the difference between ascending and descending tracts in the spinal cord?

Ascending tracts carry sensory information to the brain, while descending tracts carry motor commands to the spinal cord.

What are neuronal pools?

Interneurons organized into functional groups of interconnected neurons.

What is an innate reflex?

A basic neural reflex that is genetically programmed and formed before birth.

What is the function of the withdrawal reflex?

To move the body away from a stimulus (pain or pressure).

What characterizes a monosynaptic reflex?

It has a single synapse, where the sensory neuron synapses directly with a motor neuron.

What happens during reciprocal inhibition in a withdrawal reflex?

Antagonistic muscles are inhibited by interneurons in the spinal cord.

What is the Babinski reflex and in whom is it normal?

A reflex seen in infants due to incomplete myelination of nerves; abnormal in adults which may indicate CNS damage.