Chapter 11: Efferent Division: Autonomic and Somatic Motor Control

These flashcards cover key concepts from the lecture on the efferent division of the nervous system, highlighting important terms and definitions related to autonomic and somatic motor control.

Efferent Division

The part of the peripheral nervous system that carries commands from the central nervous system to muscles and glands.

Somatic Motor Neurons

Neurons that control skeletal muscles and are mostly voluntary.

Autonomic Neurons

Neurons that control smooth muscle, cardiac muscle, many glands, and some adipose tissue; primarily involuntary.

Sympathetic Branch

Part of the autonomic nervous system associated with the 'fight-or-flight' response.

Parasympathetic Branch

Part of the autonomic nervous system associated with 'rest-and-digest' functions.

Autonomic Reflex

Involuntary responses that maintain homeostasis, often integrated in the brain or spinal cord.

Preganglionic Neuron

The first neuron in the autonomic pathway whose cell body is located in the CNS.

Postganglionic Neuron

The second neuron in the autonomic pathway that projects to the target tissue.

Vagus Nerve

The cranial nerve that contains about 75% of all parasympathetic fibers and is crucial for heart and digestive function.

Neuroeffector Junction

The synapse between a postganglionic autonomic neuron and its target cell.

Cholinergic Neurons

Neurons that release acetylcholine (ACh) as their primary neurotransmitter.

Adrenergic Neurons

Neurons that release norepinephrine (NE) as their primary neurotransmitter.

Antagonistic Control

A regulatory mechanism where one autonomic branch is excitatory, and the other is inhibitory, maintaining balance in organ function.

Acetylcholinesterase (AChE)

The enzyme responsible for breaking down acetylcholine in the synaptic cleft.

Muscarinic Receptors

Cholinergic receptors on target cells stimulated by acetylcholine.

Adrenergic Receptors

Receptors that respond to norepinephrine and epinephrine, involved in sympathetic responses.

Catecholamines

Hormones such as norepinephrine and epinephrine, released from the adrenal medulla.

Homeostasis

The dynamic balance of physiological processes to maintain a stable internal environment.

Neuromuscular Junction (NMJ)

The synapse between a somatic motor neuron and a skeletal muscle fiber.

Chronic Exposure

Continuous presence of a stimulus, often leading to receptor adaptation or changes in cell response.