Spinal Cord, Somatic Nervous System and Reflexes

These flashcards cover key concepts related to the spinal cord, somatic nervous system, reflexes, and the associated anatomical structures and functions.

What is the function of white matter in the spinal cord?

White matter contains large numbers of myelinated and unmyelinated axons organized into columns that contain ascending and descending tracts.

What are the three types of neurons in somatic sensory pathways?

First-order neuron, second-order neuron, and third-order neuron.

What is a reflex arc?

A negative feedback loop that includes a sensory receptor, sensory neuron, integration center, motor neuron, and effector.

Classify reflexes based on processing location.

Reflexes can be classified as spinal or cranial based on where processing occurs.

What are the different classifications of reflexes?

Reflexes can be classified by development (innate, acquired), location of processing (spinal, cranial), response (somatic, visceral), and complexity (simple, complex).

What is the role of upper motor neurons?

Upper motor neurons are part of the descending tracts that send signals from the brain to lower motor neurons.

Which part of the spinal cord contains sensory nuclei?

Sensory nuclei are located in the posterior gray horns of the gray matter.

What is reciprocal inhibition in the context of reflexes?

Reciprocal inhibition is a reflex that relaxes one muscle while contracting its antagonist during a movement.

What is meant by decussation in the nervous system?

Decussation refers to the crossing over of nerve fibers to the opposite side of the body.

Explain the significance of the patellar reflex.

The patellar reflex, also known as the knee-jerk reflex, is essential for posture control and coordination of movement.