ingestion
the process of taking food, drink, or another substance into the body by swallowing or absorbing it
secretion
the release of water, acids, enzymes, buffers, and. Salts. (saliva, chyme, enzymes)
motility
movement
peristalsis
· propulsion (pushing towards anus)
· pharynx, esophagus, stomach, small intestine, large intestine, and rectum
segementation
· Keeps on squishing/mixing in a localized place
· Small intestine
haustral churning
· Large intestine
· Slow contractions of haustra to facilitate churning and squeezing out moisture
Ø For water resorption
digestion
Ø Mechanical or chemical break down of substances to be used in the body
Ø Completion of digestion is in small intestine
absorption
Small intestine- mostly nutrients
Large intestine- water
defecation
Elimination of feces from digestive tract through anus
GI tract
Ø Mouth
Ø Pharynx
Ø Esophagus
Ø Stomach
Ø Small intestine
Ø Large intestine
Ø Anal canal
accesory digestive organs
aids in ingestion, digestion, and absorption, but does not touch the food
Ø Teeth (know the 4 types of teeth and their uses)
Ø Tongue
Ø Salivary glands
Ø Liver
Ø Gallbladder
Ø Pancreas
bolus
wad of food that is mixed with saliva
chyme
The bolus is now called chyme when it is mixed with gastric acids in the stomach
lumen
cavity
Mucosa
The innermost layer of the human digestive tract; secrete digestive enzymes
gastric pits
Gastric glands that release secretions into the stomach
gastric glands
secrete gastric juice
cheif cells
secrete pepsinogen and gastric lipase
parietal cells
secrete HCl and intrinsic factor
intestinal crypts
found in the mucosa of the small intestine; produces intestinal juice
circular folds
deep folds of the mucosa and submucosa that extend completely or partially around the circumference of the small intestine
absorptive cells
Intestinal cells that line the villi; and participate in nutrient absorption
goblet cells
secrete mucus
villi
Tiny finger-shaped structures that cover the inner surface of the small intestine and provide a large surface area through which digested food is absorbed
Microvili
increase surface area for absorption
Peyer's patches
the numerous areas of lymphoid tissue in the wall of the small intestine that are involved in the development of immunity to antigens present there.
Submucosa
A layer of the human digestive system that contains nerves, blood vessels, and lymph nodes
Muscularis
the muscular layer of a hollow organ or tube
Serosa
outermost layer
mouth (oral cavity)
opening where food enters the body and undergoes the first process of digestion
lips
form the opening to the oral cavity
hard palate
roof of the mouth
soft palate
muscular posterior (back) portion of the palate
uvula
soft tissue hanging from the middle of the soft palate
tongue
manipulates food for chewing and swallowing; a taste organ
Pharynx
throat; passageway for food to the esophagus and air to the larynx
oropharynx
the area directly posterior to the mouth
laryngopharynx
lower part of the pharynx, just below the oropharyngeal opening into the larynx and esophagus
esophagus
A muscular tube that connects the mouth to the stomach.
upper esophageal sphincter
prevents backflow of food from esophagus back into mouth
gastroesophageal sphincter
separates the esophagus from the stomach
stomach
A muscular and elastic sac that serves mainly to store food, break it up mechanically, and begin chemical digestion of proteins and fat
cardiac region of stomach
surrounds the cardiac orifice
fundus region of stomach
bulge above the esophageal opening
pyloric region of stomach
lower portion of the stomach
lesser curvature
concave medial surface of the stomach
greater curvature of stomach
convex lateral surface of the stomach
rugae of stomach
let stomach expand when full
gastric juice
A digestive fluid secreted by the stomach
pyloric sphincter (of stomach)
Controls passage of food from stomach to small intestine
mesentery
structure that suspends the small intestine from the posterior body wall
lesser omentum
attaches stomach to liver
greater omentum
a fatty sheet that hangs like an apron over the abdominal viscera
small intestine
The part of the digestive system in which most chemical digestion takes place
duodenum
first portion of the small intestine
jejumun
middle of small intestine
ileum
the last and longest portion of the small intestine
brush border enzymes
break down double sugars into simple sugars and complete protein digestion
ileocecal valve
prevents food from moving back into the small intestine once it has entered the large intestine
large intestine
Absorbs water and forms feces
cecum
a pouch connected to the junction of the small and large intestines.
appendix
blind pouch hanging from the cecum
ascending colon
portion of the colon that extends upward from the cecum
transverse colon
the middle part of the large intestine, passing across the abdomen from right to left below the stomach
descending colon
portion of the colon that extends downward from the transverse colon
sigmoid colon
an S-shaped structure that continues from the descending colon above and joins with the rectum below
rectum
the final section of the large intestine, terminating at the anus
anal canal
region, containing two sphincters, through which feces are expelled from the body
internal anal sphincter
smooth muscle, involuntary
external anal sphincter
skeletal muscle, voluntary
haustra
pouches of the large intestine that allow expansion and elongation
anus
terminal end or opening of the digestive tract to the outside of the body
teeth
hard bony projections in the jaws for masticating (chewing) food
incisors
Front teeth used for cutting
canines (cuspids)
Teeth in front of the premolars that rip and tear food.
premolars (bicuspids)
broad crowns with rounded cusps used to grind or crush
molars (tricuspids)
Tooth type with a large flat surface and three grinding cusps
salivary glands
Glands of the mouth that produce saliva, a digestive secretion
parotid
the parotid gland is the salivary gland beside the ear
submandibular salivary gland
a salivary gland inside the lower jaw on either side that produces most of the nocturnal saliva
sublingual gland
salivary gland under the tongue
saliva
softens food in the mouth making it easier to swallow; helps break down food into simpler forms; secreted by glands in the mouth