Peripheral Nervous System

These flashcards contain key vocabulary terms and their definitions related to the Peripheral Nervous System and sensory receptors, based on the lecture notes.

Peripheral Nervous System (PNS)

All neural structures outside the brain, including cranial and spinal nerves.

Sensory receptors

Specialized structures that respond to changes in their environment, resulting in graded potentials that can trigger nerve impulses.

Mechanoreceptors

Sensory receptors that respond to touch, pressure, vibration, stretch, and itch.

Thermoreceptors

Sensory receptors sensitive to changes in temperature.

Photoreceptors

Sensory receptors that respond to light energy, found in the retina.

Chemoreceptors

Sensory receptors that respond to chemicals, such as in smell and taste.

Nociceptors

Sensory receptors sensitive to pain-causing stimuli.

Exteroceptors

Sensory receptors that respond to stimuli arising outside the body, like in the skin.

Interoceptors

Sensory receptors that respond to stimuli from internal organs, blood vessels, and are sensitive to chemical changes.

Proprioceptors

Sensory receptors that inform the brain of one's movements by detecting stretch in muscles, tendons, and joint structures.

Adaptation of Sensory Receptors

The process where sensory receptors become less responsive to an unchanging stimulus.

Cranial Nerves

Twelve pairs of nerves associated with the brain, primarily mixed in function.

Olfactory Nerve (I)

Sensory nerve that carries impulses for the sense of smell.

Optic Nerve (II)

Sensory nerve that carries impulses for vision.

Oculomotor Nerve (III)

Primarily motor nerve that innervates extrinsic eye muscles.

Trigeminal Nerve (V)

Mixed nerve that conveys sensory impulses from the face and supplies motor fibers for mastication.

Vagus Nerve (X)

Mixed nerve extending beyond the head and neck, involved in autonomic functions of thoracic and abdominal organs.

Reflex Arc

A neural pathway that mediates reflex actions, consisting of a receptor, sensory neuron, integration center, motor neuron, and effector.