Overview of the Autonomic Nervous System

Autonomic Nervous System

Controls involuntary body functions unconsciously.

Sympathetic Nervous System

Activates fight-or-flight responses during stress.

Parasympathetic Nervous System

Responsible for rest-and-digest body processes.

Enteric Nervous System

Regulates gastrointestinal functions independently.

Homeostasis

Maintaining stable internal body conditions.

Neurons

Cells that transmit signals in the nervous system.

Glial Cells

Support cells that assist neurons.

Nuclei

Clusters of nerve cells with similar functions.

Ganglia

Groups of related nerve cells in proximity.

Fight-or-Flight Response

Physiological reaction to perceived danger.

Rest-and-Digest Response

Body processes that promote relaxation and digestion.

Acetylcholine (ACh)

Neurotransmitter involved in autonomic nervous system signaling.

Nicotinic Receptors

Ligand-gated ion channels activated by acetylcholine.

Chemical Synapse

Site where neurotransmitters transmit signals between neurons.

Electrical Synapse

Direct cell-to-cell communication via gap junctions.

Graded Potentials

Changes in membrane potential varying in magnitude.

Depolarizing Potential

Occurs when Na+ or Ca2+ enters the cell.

Hyperpolarizing Potential

Occurs when K+ leaves or Cl- enters the cell.

Ciliary Muscles

Muscles that control lens shape for vision.

Peristalsis

Wave-like muscle contractions aiding digestion.

Pupil Constriction

Reduces pupil size for better near vision.

Bronchiolar Constriction

Narrowing of air passages in response to low oxygen.

Salivary Gland Secretion

Stimulated by parasympathetic nervous system for digestion.

Neurotransmitter

Chemical messenger transmitting signals across synapses.