7-large intestine

Question 1

what is the ileocecal valve

Answer 1

sphincer between cecum and iluem

Question 2

when is the ileocecal valve closed

Answer 2

when large intestine distended

Question 3

what is the cecum

Answer 3

appendix, no function

Question 4

what are the 4 parts of the colon

Answer 4

ascending
transverse
descending
sigmoidal

Question 5

what are the major functions of the colon

Answer 5

reabsorb water, resevoir for wase, abrob products of bacterial metabolism

Question 6

what is rectum

Answer 6

resevoir

Question 7

what is anus

Answer 7

two sphincters that control defacation (one smooth and one skeletal muscle)

Question 8

difference with external and internal anal sphincter

Answer 8

external= skeletal

interal=smooth

Question 9

does the large intestine have crypts

Answer 9

yes

Question 10

does the large intestine have villi

Answer 10

no

Question 11

what 4 types of stem cell differentiation

Answer 11

absorptive (no brush border)
goblet (lots)
few paneth and endocrine

Question 12

what do the bacteria in the colon help with (2)

Answer 12

liberate short chain fatty acids from dietary fibre

produce vitamins

Question 13

what influences water absorption in the large intestine

Answer 13

Na+ gradients made from Na+/K+ ATPase

Question 14

what influences water secretion in the large intestine

Answer 14

Cl- gradients made by secondary active transport (same as small intestine)

Question 15

purpose of large intestine motility

what type motility

Answer 15

mix contents

segmentation

Question 16

what is propulsion and when does it happen

Answer 16

3-4 times daily (after eat before poop)

intense waves of contraction that spreads over large intestine

Question 17

defection reflex

Answer 17

Rectum contracts, internal anal sphincter relaxes and
outer anal sphincter contracts (initially). Increased peristaltic
activity in the sigmoid colon, increasing pressure results in reflex
relaxation of the external anal sphincter. Feces voided.