ANS Labs

Question 1

What are the neurons of the enteric nervous system split into?

Answer 1

Plexuses.

Question 2

What are the plexuses of the enteric nervous system and where are they?

Answer 2

Myenteric plexus - found between the circular and longitudinal smooth muscle layers of the wall of the gastrointestinal tract.
Submucosal plexus - found in the submucosal layer of the gastrointestinal tract.

Question 3

How do the parasympathetic and sympathetic nervous systems influence the gut?

Answer 3

They synapse onto the enteric nervous system, not directly onto smooth muscle and glands.

Question 4

What is the neurotransmitter present at the pre to post ganglionic synapse of the sympathetic nervous system?

Answer 4

Acetylcholine.

Question 5

What is the neurotransmitter present at the pre to post ganglionic synapse of the parasympathetic nervous system?

Answer 5

Acetylcholine.

Question 6

What is the neurotransmitter present at the post ganglionic synapse of the sympathetic nervous system?

Answer 6

Mostly Noradrenaline. Sometimes acetylcholine (eg in sweat glands).

Question 7

What is the neurotransmitter present at the post ganglionic synapse of the parasympathetic nervous system?

Answer 7

Acetylcholine.

Question 8

Which contains the middle amount of neurons, the brain, the enteric nervous system or the spinal cord?

Answer 8

The enteric nervous system. Much less than brain (one thousandth) but considerably more than spinal cord. Enteric system contains one hundred million neurons.