Autonomic Nervous System Flashcards

Flashcards about the structure and function of the autonomic nervous system.

What part of the nervous system regulates smooth muscle, cardiac muscle, and certain glands?

The autonomic nervous system (ANS)

What brain regions primarily regulate the autonomic nervous system?

The hypothalamus and brain stem

What type of neurons does the somatic nervous system include?

Sensory and motor neurons

What are the two main branches of the output (motor) part of the ANS?

The sympathetic and the parasympathetic division

What neurotransmitter is used in the somatic nervous system?

Acetylcholine

What neurotransmitters are used in the autonomic nervous system?

Acetylcholine or norepinephrine

What is another name for the sympathetic division of the ANS, and why?

The thoracolumbar division, because the outflow of sympathetic nerve impulses comes from the thoracic and lumbar segments of the spinal cord.

Where are parasympathetic ganglia located?

Near or within autonomic effectors; they are called terminal ganglia.

What is another name for the parasympathetic division?

Craniosacral division

What chemical substances are released by neurons at synapses?

Neurotransmitters

Which ANS neurons release acetylcholine?

All sympathetic and parasympathetic preganglionic neurons, all parasympathetic postganglionic neurons, and a few sympathetic postganglionic neurons.

What neurotransmitter do most sympathetic postganglionic neurons release?

Norepinephrine (NE)

Activation of the sympathetic division and release of hormones by the adrenal medullae are collectively called what?

The fight-or-flight response

What activities does the parasympathetic division enhance?

Rest-and-digest activities

What is the effect of sympathetic stimulation on sweat glands?

Increased sweating

What is the effect of parasympathetic stimulation on the lacrimal (tear) glands?

Secretion of tears

Does sympathetic stimulation increase or decrease heart rate?

Increase

Does parasympathetic stimulation increase or decrease heart rate?

Decrease

What is the effect of sympathetic stimulation on the radial muscle of the iris of the eye?

Dilation of pupil

What is the effect of parasympathetic stimulation on the circular muscle of the iris of the eye?

Constriction of pupil