Nervous System Overview Quiz

Study Notes

Nervous System

Comprises the central nervous system (CNS) and peripheral nervous system (PNS).

Central Nervous System

Includes the brain and spinal cord.

Peripheral Nervous System

Encompasses all nerves and sensory structures outside the brain and spinal cord.

Somatic Nervous System

Governs voluntary control over skeletal muscles.
Utilizes acetylcholine (ACh) as the neurotransmitter.
Functions in an excitatory manner only.
Consists of a single neuron pathway from the CNS to the effector organ.

Autonomic Nervous System

Manages involuntary control of glands and smooth muscles, covering all other organ systems.
Can use either ACh or norepinephrine (NE) as neurotransmitters.
Exhibits both excitatory and inhibitory effects.
Involves two neurons from the CNS to the effector organ, with ACh at the first synapse (ganglion) and either ACh or NE at the second synapse with the organ.

Ganglion

A cluster of nerve cell bodies (grey matter) located within the peripheral nervous system.

Sympathetic Division Function

Known for "fight or flight" responses, mobilizing energy during stress.
Generally increases body activity.
Increases heart rate (HR), blood pressure (BP), and respiratory rate (RR).
Redirects blood flow to skeletal muscles and reduces flow to the digestive system, decreasing digestive activity.
Utilizes norepinephrine (NE) at the organ level for effect.

Exception to the 2-Neuron Rule

The adrenal medulla is directly stimulated by the sympathetic division.
This stimulation releases epinephrine (epi) into the bloodstream, enhancing and prolonging sympathetic effects.

Parasympathetic Division Function

Facilitates "rest and digest" processes, focusing on energy storage.
Generally decreases body activity.
Decreases HR, BP, and RR.
Increases blood flow to the digestive system and enhances digestive activity.
Utilizes acetylcholine (ACh) at the organ level.

Location of Preganglionic Soma

Sympathetic division: thoracolumbar origin (thoracic and lumbar spinal cord).
Parasympathetic division: craniosacral origin (brainstem and sacral spinal cord).

Length of Preganglionic Axon

Sympathetic division: features short preganglionic axons.
Parasympathetic division: characterized by long preganglionic axons.

Location of Ganglia

Sympathetic division: ganglia are located close to the spinal cord and far from target organs.
Parasympathetic division: ganglia are situated far from the spinal cord and close to target organs.

Length of Postganglionic Axon

Sympathetic division: long postganglionic axons that primarily use norepinephrine (NE).
Parasympathetic division: short postganglionic axons that primarily utilize acetylcholine (ACh).

Description

Test your knowledge of the nervous system with this informative quiz covering key definitions and components. From the central and peripheral nervous systems to somatic responses, you'll reinforce your understanding of how these systems function. Perfect for students of biology or health sciences.