Peripheral Nervous System Overview

These flashcards cover key terms and definitions from the lecture notes on the Peripheral Nervous System, its components, and functions.

Peripheral Nervous System (PNS)

The part of the nervous system that transmits signals between the central nervous system and the rest of the body.

Cranial Nerves

The 12 pairs of nerves that emerge directly from the brain and brainstem, responsible for various functions.

Spinal Nerves

Nerves that arise from the spinal cord and connect to various parts of the body.

Sensory Receptor Cells

Cells that transduce environmental stimuli into receptor potentials.

Mechanoreceptors

Sensory receptors that respond to mechanical pressure or distortion.

Nociceptors

Sensory receptors that respond to painful stimuli; they signal pain to the brain.

Exteroceptors

Sensory receptors that monitor external stimuli.

Interoceptors

Sensory receptors that monitor internal body stimuli.

Proprioceptors

Receptors located in muscles and joints that provide information about body position.

Receptive Fields

The total area monitored by a single sensory neuron; smaller fields enhance localization of stimuli.

Reflex Arc

The neural pathway that mediates a reflex action; involves sensory and motor neurons.

Monosynaptic Reflex

A reflex that involves a single synapse between a sensory neuron and a motor neuron.

Polysynaptic Reflex

A reflex that involves one or more interneurons in addition to the sensory and motor neurons.

Patellar Tendon Reflex

A monosynaptic reflex that causes the quadriceps muscle to contract in response to a tap on the patellar tendon.

Flexion Reflex

A protective reflex that causes the withdrawal of a limb from a painful stimulus.

Crossed-Extension Reflex

A reflex that helps maintain balance by extending the opposite limb when one limb is withdrawn.