Gastrointestineal System

Uvula

________- helps to close the entrance to the nasopharynx during swallowing.

Microvilli

________ increase the surface area of the small intestines by 20 times.

Epithelium

________ is simple columnar with microvilli → the cells are called enterocytes.

Absorption

________: uptake of digested nutrients into blood and lymph vessels.

protect mucosa of duodenum

Function: ________ from acid in chyme.

Digestive tract

________: mouth pharynx, esophagus, stomach small intestine, large intestine, rectum, anus.

Mechanical

________: crushing by teeth, mixing of food in stomach and intestines.

Villi

________ are upwards foldings of the epithelium (small intestine)

Enterocytes

________ absorb digested material and secrete some digestive enzymes.

Lingual tonsils

________ are located on the posterior aspect of the tongue.

Chemical

________: enzymatic breakdown of food in mouth, stomach and primarily small intestines.

Alimentary Calnal

________: Tube That Extends From The Mouth To The Anus.

Gastric Pits

________: contain 2- 3 tubular glands.

Gastric glands

________ in body and fundus: secrete HCl, enzymes, hormones….

small folds

The lineing is in ________ that form small peaks called Villi that help absorb nutirents.

soft palate

Hard and ________- roof of mouth (hard palate: palatine process of maxillary bone and palatine bones)

Microvilli

________ (small and large intestines) are projections on the surface of individual enterocytes (cells of the intestinal epithelium)

Ingestion

mouth

Digestion

starts in mouth

Mechanical

crushing by teeth, mixing of food in stomach and intestines

Chemical

enzymatic breakdown of food in mouth, stomach and primarily small intestines

Absorption

uptake of digested nutrients into blood and lymph vessels

Tube that extends from mouth to anus

considered external

Digestive tract

mouth pharynx, esophagus, stomach small intestine, large intestine, rectum, anus

Accessory organs (not part of alimentary canal)

teeth, tongue, salivary glands, liver, gallbladder, pancreas

Fauces

entrance to pharynx

Uvula

helps to close the entrance to the nasopharynx during swallowing

From C6/cricoid cartilage to T7

enters stomach

Deglutition

(swallowing)

swallowing center

paired nuclei in medulla oblongata

Glands of the Stomach

Gastric Pits

Gastric Pits

contain 2-3 tubular glands

Cardiac and pyloric glands in cardia and pylorus regions

mainly mucus-secreting (protect esophagus and duodenum)

Gastric glands in body and fundus

secrete HCl, enzymes, hormones…

Parietal cells

HCl, intrinsic factor (B12 absorption)

Chief cells

pepsinogen (converted to active form in presence of HCL → pepsin)

Small intestine

digestion, absorption

Three parts

duodenum, jejunum, ileum

Finger-like projections of the epithelium into the lumen of the small intestines

up to 1.0mm long

First part of the small intestine

distal to the stomach (-10 inches)

Function

protect mucosa of duodenum from acid in chyme

contains Peyers patches

clusters of lymphatic tissue

Large Intestines

- aka Colon

Longitudinal muscularis externa muscles form the 3 taeniae coli**

** because they are shorter than the colon, they cause the colon to sacculate and form pouches called haustra

Internal anal sphincter

smooth muscle

External anal sphincter

skeletal muscle

Alimentary Calnal

Tube That Extends From The Mouth To The Anus

Large

Cecum, Rectum, Anal Cavity

Small

Duodenum, Jejunum, Ileum

Internal

Involuntary Smooth Muscle Located Distally To The GI Tract

External

Voluntary Muscle Around The Anal Cavity and Anal Opening

Lingual Lapase

Breaks Down Fats

Large

Five Feet

Small

Twenty Feet