Autonomic Physiology 1

Question 1

What is the purpose of the autonomic nervous system?

Answer 1

To control involuntary actions

Question 2

What does the autonomic nervous system control?

Answer 2

• smooth muscle surrounding blood vessels, airways, bladder, gut and sex organs
• secretions from glands
• focussing of the eye

Question 3

How can the autonomic nervous system be divided?

Answer 3

Sympathetic system and

Parasympathetic system

Question 4

What does the somatic nervous system act on?

Answer 4

Skeletal muscle

Question 5

What does the autonomic nervous system act on?

Answer 5

Smooth muscle

Cardiac muscle

Glands

GI neurones

Question 6

Describe the structure of a nerve fibre in the autonomic nervous system?

Answer 6

Pre-ganglionic fibre (small myelinated)

• Ganglion
• Post-ganglionic fibre(unmyelinated)
• Receptor

Question 7

What is true of somatic nervous system receptors?

Answer 7

• specialised NMJ
• ionotropic receptors
• always excites target

Question 8

What is true of autonomic nervous system receptors?

Answer 8

• less specialised junction
• metabotropic receptors
• may excite or inhibit target

Question 9

What is the sympathetic nervous system responsible for?

Answer 9

Fight or flight

Question 10

What is the parasympathetic nervous system responsible for

Answer 10

Rest and digest

Question 11

Where does the sympathetic nervous system exit the spinal cord?

Answer 11

Thoracic 1-12

Lumbar 1-2

Question 12

Describe a sympathetic nerve fibre.

Answer 12

Ganglia lie close to spinal cord in the sympathetic trunk (paravertebral ganglia) or in collateral ganglia (prevertebral ganglia)

Question 13

What do convergence and divergence lead to?

Answer 13

Mass activation

Question 14

Name 2 autonomic neurotransmitters.

Answer 14

Acetylcholine

Noradrenaline

Question 15

What receptors does acetylcholine act on?

Answer 15

Cholinergic receptors (nicotinic/muscarinic)

Question 16

What receptors does noradrenaline act on?

Answer 16

Adrenergic receptors (a/B)

Question 17

Sympathetic Nervous System: What do preganglionic fibres release?

Answer 17

Acetylcholine which act on nicotinic cholinergic receptors

Question 18

Sympathetic Nervous System: What do postganglionic fibres release?

Answer 18

Noradrenaline which acts on a or B adrenergic receptors

Question 19

What happens at the post-ganglionic cells of adrenal medulla in the sympathetic nervous system?

Answer 19

They have no axons so they release adrenaline and noradrenaline into the blood

Question 20

Where does the parasympathetic nervous system exit the spinal cord?

Answer 20

Cranial 3,7,9,10

S2-4

Question 21

Describe a parasympathetic nerve.

Answer 21

Ganglia lie close to or within the target.

Question 22

Parasympathetic nervous system: What do the preganglionic fibres release?

Answer 22

Acetylcholine which acts on nicotinic cholinergic receptors

Question 23

Parasympathetic nervous system: What do the postganglionic fibres release?

Answer 23

Acetylcholine which acts on muscarinic cholinergic receptors

Question 24

What do postganglionic sympathetic cholinergic fibres do?

Answer 24

Innervate sweat glands

Question 25

What do some postganglionic fibres do?

Answer 25

Release non-adrenergic non-cholinergic transmitters (NANC) e.g. peptides or NO