Chapter 16: The Autonomic Nervous System

These flashcards cover key concepts and terms related to the Autonomic Nervous System as described in Chapter 16 of Human Anatomy.

Autonomic Nervous System (ANS)

A visceral motor system that controls involuntary actions of effectors like glands, cardiac muscle, and smooth muscle.

Visceral Reflexes

Unconscious, automatic responses of visceral effectors to stimuli, such as a decrease in heart rate triggered by a rise in blood pressure.

Sympathetic Division

Part of the ANS responsible for 'fight-or-flight' responses, increasing heart rate and blood glucose, and reducing blood flow to skin and GI tract.

Parasympathetic Division

Part of the ANS responsible for 'rest and digest' responses, decreasing heart rate, and stimulating digestion and waste elimination.

Autonomic Tone

The balance between the activity of the sympathetic and parasympathetic nervous systems.

Preganglionic Fiber

A fiber with its neurosoma located in the brainstem or spinal cord that terminates in a ganglion.

Postganglionic Fiber

A fiber with its neurosoma in a ganglion, extending to the target organ.

Somatic Nervous System

Part of the nervous system that controls voluntary movements of skeletal muscles.

Enteric Nervous System

A part of the ANS that innervates smooth muscle and glands in the digestive tract, regulating motility and secretion.

Horner Syndrome

A disorder characterized by unilateral pupillary constriction, sagging of eyelid, and flushing of skin, linked to lesions in the sympathetic division.

Raynaud Disease

A disorder manifesting as paleness, cyanosis, and pain in digits when cold or stressed, due to excessive vasoconstriction.