GI A&P Flashcards
Review the old biomed and anatomy GI Lectures
:)
The esophageal mucosa is different than
the rest of the GI tract: it is composed of
thick, ______
stratified squamous epithelium
The esophagus passes through the ____
of the diaphragm
Esophageal Hiatus
As the esophagus connects to the stomach, the mucosa changes from
____ to secretory ____
squamous cells; columnar epithelium
What is the junction called where the mucosa of the esophagus changes?
Squamocolumnar Junction (important with GERD, cancer)
The Chyme in the stomach then passes
through the _____, a thick layer of smooth
muscle that regulates entry of material into the duodenum
Pyloric Sphincter
The stomach lining is composed of numerous fold called ____
Gastric Rugae
Pyloric stenosis can lead to____
projectile vomitting (babies)
What do the rugae do for the stomach?
allow the stomach to expand significantly when
food enters, and then return to the normal J-shape when it is empty again
Surface Mucous Cells secrete ____
mucin (Mucus)
Mucous Neck Cells also secrete ____ to
protect the gland itself from the acid.
mucin
Parietal Cells produce _____
which denatures proteins
Hydrochloric Acid (ph 2.0)
Chief Cells secrete ____- denatures proteins
Pepsinogen (which becomes
Pepsin)
Enterochromaffin-Like Cells (ECL Cells) secrete
_____, which activates Parietal Cells.
Histamine
D Cells secrete ______
somatostatin
____ is the first 25 cm of the small intestine
The Duodenum
Inside the villi are rich
networks of _____
capillaries composed of Venules,
Arterioles, and Lacteals
Explain why there is a countercurrent blood flow in the intestinal villi
the close proximity of arterial and
venous blood results in a shunting of oxygen, with up to 80% of oxygen bypassing the villi epithelium
Layers of the GI wall
○ Mucosa: is in contact with food, absorption of nutrients
○ Submucosa: contains blood vessels,
lymphatic vessels, and nerves
○ Muscularis
■ Longitudinal Smooth Muscle
■ Circular Smooth Muscle
○ Serosa: Protective connective Tissue
the primary region for
nutrient absorption
Jejunum
T/F the Jejunum and Illeum are both completely
intraperitoneal and is suspended in the abdomen by the mesentery
T
Importance of the ileocecal valve
Acts as a sphincter that
primarily prevents fecal contents
from the colon from going back
into the small intestines