Autonomic Nervous System (ANS) Function

Which of the following is NOT a characteristic of the Autonomic Nervous System (ANS)?

Which of the following is the main location of the ANS centers that activate the autonomic nervous system?

What is the term for the phenomenon where most viscera receive nerve fibers from both the sympathetic and parasympathetic divisions?

Which of the following spinal nerves are involved in the sympathetic nervous system?

What is the neurotransmitter released by the post-ganglionic neuron in the parasympathetic nervous system?

Which of the following cranial nerves is NOT involved in the parasympathetic nervous system?

What percentage of all parasympathetic nerve fibers are found in the vagus nerves?

Which of the following is a function of the Somatic Nervous System?

Autonomic Nervous System (ANS)

Controls visceral functions of the body, including:
- Arterial pressure
- Gastrointestinal motility
- Gastrointestinal secretion
- Sweating
- Body temperature

Characteristics of ANS

Rapid response (within 3-5 seconds) and intensity
Can increase heart rate to twice normal within 3-5 seconds

Effect of ANS

Mainly affects:
- Smooth muscle
- Glands
- Cardiac muscle

Comparison with Somatic Nervous System (SNS)

SNS only affects skeletal muscle
SNS effects skeletal muscle directly via motor nerve

Centers and Effects of ANS

ANS centers located in:
- Spinal cord
- Brain stem
- Hypothalamus
Two major subdivisions of ANS:
- Sympathetic Nervous System (SNS)
- Parasympathetic Nervous System (PNS)

Sympathetic Nervous System (SNS)

SNS originates in:
- Thoraco-lumbar spinal cord (T1-L2)
Short pre-ganglionic fibers from spinal cord synapse with:
- Paravertebral ganglions (close to spinal cord)
- Prevertebral Celiac or epigastric ganglion
Long post-ganglionic fibers then send signals to affected side

Neurotransmitters and Receptors of SNS

Pre-ganglionic nerve secretes:
- Acetylcholine (Ach)
Post-ganglionic neuron secretes:
- Either Acetylcholine (Ach) or Norepinephrine (NE)

Parasympathetic Nervous System (PNS)

PNS originates from:
- Cranial nerves (III, VII, IX, and X)
- 1-4 sacral spinal nerves
About 75% of all parasympathetic nerve fibers are in the:
- Vagus nerve (cranial nerve X)

This quiz covers the autonomic nervous system, its characteristics, and effects on various muscle types and glands. Study the ANS' role in controlling visceral functions, heart rate, and more.