Chp 15 a&p

Sympathetic Division

Part of the autonomic nervous system associated with the fight-or-flight response, affecting multiple organ systems simultaneously.

Parasympathetic Division

Part of the autonomic nervous system associated with rest and digest functions, primarily influencing organs through localized actions.

Dual Innervation

The presence of both sympathetic and parasympathetic fibers innervating the same target organ, allowing for balanced control.

Craniosacral System

Alternate term for the parasympathetic division due to its origin from brainstem nuclei and the sacral spinal cord.

Thoracolumbar System

Alternate term for the sympathetic division reflecting its anatomical origin from the thoracic and upper lumbar spinal cord.

Cholinergic Synapses

Synapses where acetylcholine (ACh) is released, involving nicotinic and muscarinic receptors.

Adrenergic Synapses

Synapses where norepinephrine is released, involving alpha and beta adrenergic receptors.

Acetylcholine (ACh)

A neurotransmitter released by all preganglionic fibers in the autonomic nervous system and postganglionic fibers of the parasympathetic division.

Norepinephrine

A neurotransmitter released by most postganglionic sympathetic fibers, involved in adrenergic signaling.

Epinephrine

A hormone released by the adrenal medulla, also known as adrenaline, important for the fight-or-flight response.

Preganglionic Fiber

The axon of a neuron that extends from the central nervous system to a ganglion.

Postganglionic Fiber

The axon of a neuron that extends from a ganglion to the target organ.

Varicosity

Swellings along the length of an autonomic fiber where neurotransmitters are released, differing from typical synapses.

Adrenergic Receptors

Receptors that bind norepinephrine or epinephrine, classified into alpha and beta types.

Muscarinic Receptors

G protein-coupled receptors that bind acetylcholine in the parasympathetic division.

Nicotine Receptors

Ligand-gated cation channels that bind acetylcholine in both divisions of the autonomic nervous system.

Homeostasis

The balance between sympathetic and parasympathetic activities in the autonomic nervous system.