large intestine

Question 1

what is the colon made up of

Answer 1

ascending
transverse
descending
sigmoid

Question 2

what does the muscle wall consist of

Answer 2

inner circular

outer longitudinal

Question 3

what is unique about the outer layer

Answer 3

comes together to form the teniae coli

Question 4

what does the teniae coli produce

Answer 4

the haustral pattern

Question 5

what is the mucosa of the colon lined with

Answer 5

epithelial cells and goblet cells

Question 6

what does the epithelium of the colon contain

Answer 6

crypts

Question 7

what cells are found in the lamina propria

Answer 7

lymphocytes and macrophages

Question 8

what is the blood supply to the colon from

Answer 8

superior and inferior mesenteric vessels

Question 9

what is the colon innervated by

Answer 9

enteric nervous system

Question 10

what autonomic chains innervate the colon

Answer 10

both

Question 11

what sphincter is there in the anal canal

Answer 11

internal and external

Question 12

what are the main roles of the colon

Answer 12

absorption of water and electrolytes
and
propulsion of contents from the caecum to the rectal region

Question 13

what is absorption stimulated by

Answer 13

short chain fatty acids that are produced in the right colon

Question 14

what do high amplitude propagative colonic contractions cause

Answer 14

propulsion

Question 15

what induces peristalsis

Answer 15

serotonin 5-HT

Question 16

is the rectum normally full or empty

Answer 16

empty

Question 17

how is stool propelled into the rectum

Answer 17

by propagated colonic contractions

Question 18

what are defecating sensations associated with

Answer 18

rectal contraction and relaxation of the internal anal sphincter

Question 19

who is most likely to get constipation

Answer 19

women and the elderly

Question 20

what is the definition of constipation

Answer 20

two or more of the following for at least 12 weeks:

• infrequent passing of stool <3
• straining >25%
• passage of hard stools
• incomplete evacuation
• sensation of anorectal blockage

Question 21

what are other symptoms with constipation

Answer 21

• abdominal bloating

- local and perianal pain

Question 22

causes of constipation

Answer 22

• inadequate fibre intake
• diabetes
• hypercalcaemia
• IBS
  drugs:
• opiates
• calcium channel blockers
• anti-depressants
  psychological:
• depression
• anorexia

Question 23

what investigations are done for constipation

Answer 23

• colonoscopy

- CT

Question 24

treatment for constipation

Answer 24

• treat underlying
• increase fibre content of diet
• increase fluid intake
• laxatives

Question 25

how do osmotic laxatives work

Answer 25

increase the colonic inflow of fluid and electrolytes - softens the stools