Nerves

Question 1

What spinal levels do the sympathetic nerves innervating the gut arise from?

Answer 1

T5 - L3

Question 2

Where do the sympathetic pre-ganglionic nerve fibres innervating the gut travel?

Answer 2

Travel through the sympathetic chain without synapsing

Question 3

What do the sympathetic pre-ganglionic nerve fibres do after travelling through the sympathetic chain?

Answer 3

Bundle together to form larger nerve fibres

Question 4

What larger nerve fibres do the sympathetic pre-ganglionic nerve fibres join together to form?

Answer 4

Greater splanchnic nerve

Lesser splanchnic nerve

Least splanchnic nerve

Question 5

Which pre-sympathetic nerve fibres join together to form the greater splanchnic nerve?

Answer 5

T5 - T9

Question 6

Which pre-sympathetic nerve fibres join together to form the lesser splanchnic nerve?

Answer 6

T10 - T11

Question 7

Which pre-sympathetic nerve fibres join together to form the least splanchnic nerve?

Answer 7

T12 on its own!

Question 8

Where does the greater splanchnic nerve travel to?

Answer 8

Travels to the coeliac ganglion

Question 9

Where does the lesser splanchnic nerve travel to?

Answer 9

Travels to the superior mesentetic ganglion

Question 10

Where does the least splanchnic nerve travel to?

Answer 10

Travels to the inferior mesenteric ganglion

Question 11

Where do the greater, lesser and least splanchnic nerves synapse with sympathetic post-ganglionic nerve fibres?

Answer 11

At their corresponding ganglion

Question 12

What do the post-ganglionic sympathetic nerve fibres from the coeliac ganglion innervate?

Answer 12

Foregut structures

mainly smooth muscle in blood vessels

Question 13

What do the post-ganglionic sympathetic nerve fibres from the superior mesenteric ganglion innervate?

Answer 13

Midgut structures

mainly smooth muscle in blood vessels

Question 14

What do post-ganglionic sympathetic nerve fibres from the inferior mesenteric ganglion innervate?

Answer 14

Hindgut structures

mainly smooth muscle in blood vessels

Question 15

What runs with sympahetic nerve fibres between the spinal cord and the gut?

Answer 15

Visceral afferent nerve fibres

Question 16

What information do visceral afferent nerve fibres carry?

Answer 16

Sensory information

• pain
• reflexes

Question 17

What carries parasympathetic innervation to the gut?

Answer 17

Vagus nerve

Pelvic splanchnic nerves

Question 18

What part of the gut does the vagus nerve innervate?

Answer 18

Foregut and midgut structures

Question 19

What part of the gut do the parasympahetic pelvic splanchnic nerves innervate?

Answer 19

Hindgut

Question 20

Where do the pelvic splanchnic nerves arise from?

Answer 20

They are parasympathetic pre-ganglionic nerve fibres

so they arise from the spinal cord

Question 21

What spinal levels do the parasympathetic pre-ganglionic pelvic splanchnic nerves arise from?

Answer 21

S2 - S4

Question 22

Where do the parasympathetic pre-ganglionic nerve fibres synapse with the post-ganglionic nerve fibres?

Answer 22

In the walls of the viscera

Question 22

What parts of the hindgut do the parasympathetic post-ganglionic nerve fibres innervate?

Answer 22

Smooth muscle in walls of gut

Glands

Question 24

Where are the right and left vagus nerves located in relation to the oesophagus and stomach?

Answer 24

Right vagus nerve is posterior

Left vagus nerve is anterior

Question 25

What is the explanation for the location of the right anf left vagus nerves in relation to the stomach?

Answer 25

Foregut rotates 90degrees clockwise during development