The Autonomic Nervous System

These flashcards cover key terms and definitions related to the autonomic nervous system discussed in the lecture.

Sympathetic Division

Part of the autonomic nervous system responsible for the body's 'fight or flight' response.

Parasympathetic Division

Part of the autonomic nervous system that promotes 'rest and digest' activities.

Efferent Pathways

Neural pathways that carry signals away from the central nervous system to effectors.

Effectors

Organs or cells that respond to motor neuron signals, including muscles and glands.

Neurotransmitters

Chemicals that transmit signals across a synapse from one neuron to another or to a target effector.

Acetylcholine (ACh)

The neurotransmitter released by somatic motor neurons and preganglionic fibers of the ANS.

Norepinephrine (NE)

A neurotransmitter released by most postganglionic fibers in the sympathetic division.

Preganglionic Neuron

Neurons originating in the CNS that extend to an autonomic ganglion.

Postganglionic Neuron

Neurons that connect the autonomic ganglion to the target effector.

Dual Innervation

A situation where an organ is innervated by both the sympathetic and parasympathetic divisions.

Homeostasis

The maintenance of stable internal conditions in the body regulated by the autonomic nervous system.

Vasoconstriction

The narrowing of blood vessels that increases blood pressure, often caused by sympathetic stimulation.

Visceral Effectors

Internal organs that are controlled by the autonomic nervous system.

Glandular Secretion

Release of substances by glands controlled by the autonomic nervous system.

Autonomic Ganglia

Clusters of nerve cell bodies in the autonomic nervous system located outside the CNS.

Central Nervous System (CNS)

The brain and spinal cord which process and transmit information.

Peripheral Nervous System (PNS)

The network of nerves that emanate from the brain and spinal cord to the rest of the body.

Somatic Nervous System

The part of the peripheral nervous system that controls voluntary movements of skeletal muscles.

Cardiac Muscle

Muscle tissue of the heart, which is controlled by the autonomic nervous system.

Smooth Muscle

Involuntary muscle found in walls of hollow organs, regulated by the ANS.

Hypothalamus

A brain region that regulates autonomic functions and homeostasis.