Digestive System Summary Notes

Question 1

main functions of the digestive system?

Answer 1

motility
digestion (duodenum)
secretion
absorption (jejumen)
excretion (exertion)

Question 2

what is motility?

Answer 2

smooth muscle contractions that are involuntary (from esophagus to rectum)

Question 3

what is digestion and were does it occur?

Answer 3

occurs in duodenum

chemical hydrolysis of polymers to monomers

Question 4

what is secretion?

Answer 4

release of various digestive juices in the lumen of the GI

Question 5

what is absorption and where does it occur?

Answer 5

nutrients moving from the GI lumen to blood vessels

occurs in jejumen

Question 6

what is excretion?

Answer 6

minor components which are indigestible

Question 7

what are the functions of the stomach?

Answer 7

production of HCl
synthesis of intrinsic factor
production of pepsinogen which turns into pepsin when in contact with stomach acid

Question 8

does absorption happen in the stomach?

Answer 8

little to none

Question 9

where does chemical digestion of starch start?

Answer 9

in the mouth

Question 10

components of small intestine?

Answer 10

duodenum
jejunum
ileum

Question 11

what does the duodenum do?

Answer 11

receives digestive juices from accessory glands (liver, pancreas, gallbladder)

Question 12

what does the small intestine do?

Answer 12

release internal signals to regulate organs in close proximity

Question 13

what does the pancreas do?

Answer 13

neutralize HCl

release various enzyme’s

Question 14

what does bile do?

Answer 14

emulsifies fat

Question 15

where does bile come from?

Answer 15

bilirubin from hemoglobin

Question 16

what does the gallbladder do?

Answer 16

concentrates bile and removes water out of bile

Question 17

what local hormones are produced by the duodenum?

Answer 17

GIP (gastric inhibitory peptide)

CCK (cholecystokinin)

Question 18

what does GIP do?

Answer 18

slows down rate of gastric emptying

travels through blood vessels

Question 19

what does CCK do?

Answer 19

stimulates pancreas, liver, gallbladder

travels through blood vessels

Question 20

segments of large intestine (colon)?

Answer 20

ascending colon
transverse colon
descending colon
sigmoid colon (leads to rectum)
rectum

Question 21

what does the large intestine do?

Answer 21

reabsorbs remaining water through osmosis by absorbing Na