Autonomic Nervous System

Question 1

What are the 2 main divisions of the nervous system?

Answer 1

Central nervous system

Peripheral nervous system

Question 2

What are the 2 main divisions of the peripheral nervous system?

Answer 2

Afferent (sensory) nerves

Efferent (motor) nerves

Question 3

What are the 2 divisions of the efferent (motor) nervous system?

Answer 3

Somatic (voluntary) nervous system

Autonomic (involuntary) nervous system

Question 4

What are the 2 divisions of the autonomic (involuntary) nervous system?

Answer 4

Parasympathetic nervous system

Sympathetic nervous system

Question 5

What areas of the spinal column do sympathetic nerves emerge from?

Answer 5

Throracolumbar outflow

Question 6

For sympathetic nerves, how does the length of preganglionic and postganglionic fibres compare?

Answer 6

Short preganglionic and long postganglionic fibres

Question 7

Where are sympathetic ganglia located?

Answer 7

Prevertebral ganglia

Paravertebral ganglia

Question 8

In the sympathetic nervous system, the synapses between pre and post-ganglionic cells are what?

Answer 8

Cholinergic and nicotinic

Question 9

In the parasympathetic nervous system, the synapses between pre and post-ganglionic cells are what?

Answer 9

Cholinergic and nicotinic

Question 10

In the parasympathetic nervous system, the fibres between post-ganglionic cells and targets are what?

Answer 10

Cholinergic and muscarinic

Question 11

What do post-ganglionic cells in the adrenal medulla release?

Answer 11

Adrenaline

Question 12

What do post-ganglionic fibres in the adrenal medullar contribute to?

Answer 12

Mass activation, being part of the sympathetic nervous system and releasing adrenaline

Question 13

What receptors do adrenaline and noradrenaline act on?

Answer 13

Adrenergic receptors

Alpha receptors

Beta receptors

Question 15

What kinds of receptors does acetycholine act on?

Answer 15

Nicotinic and muscarinic receptors

Question 16

In the eye, what does sympathetic activation cause?

Answer 16

Contraction of the radial muscle of the iris (pupil dilates)

Relaxation of the ciliary muscle surrounding the lens (eye focuses further away)

Question 17

What do eye drops used to dilate the pupil often contain?

Answer 17

Muscarinic antagonist

Alpha 1 agonist

Question 18

What does the parasympathetic system cause in the heart?

Answer 18

Release of acetylcholine

Decrease in heart rate

Question 19

In blood vessels, what does the sympathetic system cause?

Answer 19

Vasocontriction, but causes vasodilation in some that express B₂ receptors

Question 20

In the lung, what does activation of the sympathetic nervous system cause?

Answer 20

Relaxation of smooth muscle

Question 21

What are some clinical applications of understanding the receptors within the ANS?

Answer 21

Side effects and contraindications of drugs affecting ANS should be predictable

Autonomic neuropathy may be the cause of syncope, bladder problems, bowel problems etc

Diagnosis and progress of disease can be monitored by tests of autonomic function, such as cardiovascular response to deep breathing, Valsalva manoeuvre and tilt test