Gastrointestinal System Flashcards
GI functions
- provide nutrients for the body with propulsive and mixing movements
- secretions of digestive juices
- absorption of nutrients
Esophagus
Tube shaped muscular conduit for food and fluids that connects the throat to the stomach
Movement through the esophagus is facilitated by
- secretion of mucus
- very strong movement to propel food towards the stomach
What are the esophageal sphincters
Upper and lower
What does the upper esophageal sphincter do?
Prevents food and fluids from being aspirated into the lungs
What does the lower esophageal sphincter do?
Also called the cardiac sphincter
- separates the esophagus from the stomach
- prevents acidic contents of the stomach from entering back into the esophagus
What is the stomach
Elastic reservoir for food, mixing and initial digestions of proteins
What is the capacity of the stomach
1000-1500 ml
What type of cells are in the stomach
Columnar epithelial with gastric glands
What types of cells are in stomach glands
Ones that secrete HCl, intrinsic factors, gastrin
What are the layer of stomach
Mucosa layer
Two muscle layers
Serosa
What cells are in the stomach’s mucosa layer
G-cells, parietal, chief, epithelial, blood vessels
What is the role of the muscle layers of the stomach
Help propel food from stomach to small intestine
What is the serosa of the stomach
Outer layer that covers the inner layers
What is a g cell
Produces gastrin
What is gastrin
A hormone that facilitates production of HCl
What is a parietal cell
Produces HCl
What does HCl do
Helps break down food
What is a chief cell
Secretes pepsin
What is the function of the epithelial cells of stomach
Secrete bicarbonate rich solution to coat and protect the mucosa
What are the sections of the small intestine
Duodenum, jejunum, ileum
What is a plicae circulares
Circular folds of a mucus membrane of the inner wall
What are intestinal villi
Finger like projections on the permanent ridges called plicae circulares
What are microvilli
Microscopic projections that like the villi