Peripheral Nervous System and Reflex Activity: BIOL 2111

Practice flashcards on key terms and definitions from the lecture on the Peripheral Nervous System and Reflex Activity.

Peripheral Nervous System (PNS)

The part of the nervous system that provides links from and to the external environment.

Sensory Receptors

Specialized cells that respond to changes in the environment and generate graded potentials that may trigger nerve impulses.

Sensation

The awareness of changes in the internal and external environment.

Perception

The conscious interpretation of stimuli.

Exteroceptors

Receptors that respond to stimuli arising outside the body, such as touch and temperature.

Interoceptors (Visceroceptors)

Receptors that respond to stimuli arising from within the body, such as chemical changes and tissue stretch.

Proprioceptors

Receptors that respond to stretch in skeletal muscles, tendons, and joints, providing information about body movements.

Graded Potential

A local change in membrane potential that varies in magnitude and can trigger an action potential if it reaches threshold.

Action Potential (AP)

A rapid rise and subsequent fall in voltage or membrane potential across a cellular membrane.

Wallerian Degeneration

The process that occurs when a peripheral axon is injured, resulting in degeneration of the distal portion of the axon.

Referred Pain

Pain perceived in a location other than the site of the painful stimulus, often due to shared neuronal pathways.

Phantom Limb Pain

Pain that feels like it's coming from a limb that has been amputated.

Olfactory Nerve (I)

Cranial nerve responsible for the sense of smell; purely sensory.

Optic Nerve (II)

Cranial nerve responsible for vision; purely sensory.

Oculomotor Nerve (III)

Cranial nerve that controls eye movement and pupil constriction; primarily motor.

Trigeminal Nerve (V)

Cranial nerve responsible for sensation in the face and motor functions such as chewing; mixed nerve.

Facial Nerve (VII)

Cranial nerve that controls facial expressions and conveys taste sensations from the anterior two-thirds of the tongue; mixed nerve.

Vestibulocochlear Nerve (VIII)

Cranial nerve responsible for hearing and balance; mostly sensory.

Vagus Nerve (X)

Cranial nerve that extends beyond the head and neck, controlling parasympathetic functions in the thorax and abdomen; mixed nerve.