Diarrhea and Constipation

Question 1

Intrinsic innervation of small intestine and colon comprises of

Answer 1

myenteric, submucosal and mucosal neuronal layers

Question 2

Functions of myenteric, submucosal and mucosal neuronal layers are regulated by

Answer 2

interneurons, through actions of amines or peptides including acetylcholine, vasoactive intestinal peptides , opioids, NE, Serotonin, ATP, NO

Question 3

Smooth muscle function is regulated by

Answer 3

Myenteric plexus

Question 4

Secretion, Absorption and Blood flow is affected by

Answer 4

Submucosal plexus

Question 5

Extrinsic innervation of small intestine and colon are part of autonomic nervous system and modulates the

Answer 5

motor and sensory functions

Question 6

Parasympathetic nerves convey

Answer 6

visceral sensory and excitatory pathways to the colon

Question 7

Parasympathetic fibers reach the small intestine and proximal colon via

Answer 7

vagus nerve, along the branches of the superior mesenteric artery

Question 8

Distal colon is supplied by

Answer 8

sacral parasympathetic nerves (S2-S4) via the pelvic plexus

Question 9

Chief excitatory neurotransmitters controlling motor functions are

Answer 9

Acetylcholine, and tachykinin such as Substance P

Question 10

Sympathetic nerve supply modulates

Answer 10

motor function and reaches the small intestine and colon alongside the arterial vessels

Question 11

Sympathetic input to the gut is usually

Answer 11

Excitatory to sphincters, Inhibitory to non sphincteric muscles

Question 12

On an avg day , ____ fluid enter the GIT

Answer 12

9 Litres

Question 13

On an avg day, ___ residual fluid reach the colon

Answer 13

about 1 Litres

Question 14

On an avg day, ____ fluid is the stool excretion

Answer 14

0.2 L/d

Question 15

In the colon, Sodium absorption is predominantly electrogenic and uptake takes place at

Answer 15

Apical membrane

Question 16

______ and _____ also influence colonic absorption

Answer 16

Angiotensin and Aldosterone

Question 17

During fasting, the motility of the small intestine is characterized by a cyclical event called

Answer 17

Migrating motor complex (MMC) — serves to clear nondigestible residue from the intestine

Question 18

MMC contractions on average lasts ____, occurs every ____ min and usually involve the entire ____

Answer 18

4 min, 60-90 min , small intestine

Question 19

Distal ileum acts as a reservoir by

Answer 19

emptying intermittently by bolus movement

Question 20

Segmentation by haustra compartmentalizes the colon and facilitates

Answer 20

mixing, retention of residue and formation of solid stools

Question 21

In normal healthy person, the ascending and transverse regions of colon functions as reservoirs with transit time of

Answer 21

average transit 15h

Question 22

descending colon acts as a conduit with transit time of

Answer 22

average transit 3 h

Question 23

Colon is efficient at conserving

Answer 23

sodium and water

Question 24

Diarrhea or constipation results from

Answer 24

Alteration in the reservoir function of the proximal colon or the propulsive function of the left colon

Question 25

Constipation might occur as a result of

Answer 25

rectal or sigmoid reservoir disturbances, typically as result of dysfunction of pelvic floor, anal sphincters or coordination of defecation

Question 26

Small intestinal MMC rarely continues into the

Answer 26

Colon