Digestive System I Chapter 13 Flashcards
The purpose of the digestive system is to ______ or break down food molecules using water
hydrolyze
Occurs when we take in food through our mouths
ingestion
involves the breakdown of larger pieces of food into smaller pieces that can be acted upon by digestive enzymes
digestion
_________digestion is when food is broken into smaller pieces by chewing
mechanical
_____ digestion is when the bonds in food are broken down by enzymes like saliva
chemical
Involves peristalsis, the smooth muscle contractions, which help pass food from one organ to the next
movement of the GI tract
Occurs as subunit molecules cross the wall of the GI tract and enter the blood
absorption
Removes molecules that cannot be digested from the body
elimination
Order of the layers in the GI tract (1 is innermost layer)
1. Lumen
2. Mucosa
3. Submucosa
4. Muscularis
5. Serosa
nice
Secretes lubricating fluid
serosa
Contains blood vessels and nerves. Carry nutrients absorbed by mucosa
submucosa
layers of perpendicular muscle, responsible for peristalsis
muscularis
secretes protective mucus
mucosa
open area that contains digested food
lumen
Begins the process of mechanical and chemical digestion
mouth
Thick walled, J shaped organ on left side of body beneath diaphragm
Extension of the esophagus
stomach
Prevents the contents of stomach from entering the esophagus
esophageal sphincter
Contractions of stomach controls secretion of chyme into small intestine at this area
Pyloric sphincter
Allows for the stomach to stretch and mechanically break down food into smaller fragments mixed with gastric juice
Oblique layer of muscle in the muscularis layer
Leads to gastric gland which produce gastric juice, which digest protein, hydrochloric acid and mucus
Gastric Pits
Very long averaging about 18 feet which consists of 3 regions
duodenum
jejunum
ileum
And contains lots of enzymes to digest
Small Intestines
Begins digestion of carbohydrates
Amylase
A potease enzyme that originates in pancreas, begins, then intestinal enzymes finish digestion of carbohydrates to glucose
Trypsin
Neutralizes chyme and causes intestine to be slightly basic (Ph)
Sodium Bicarbonate
Walls of small intestine absorbs sugar, amino acid, glycerol, and fatty acid molecules produced by digestive process
mucosa absorbs
absorption
Disorder where you don’t have the brush border enzyme lactase so you can’t digest lactose
Lactose Intolerance
Disorder caused by autoimmune response against protein called gluten
Presence of gluten in small intestine results in inflammatory response, damaging parts of small intestine
Celiac Disease
Disorder where inflammation of irregular bulging pouches in wall of large intestine
Diverticulosis
