Anatomy Flashcards
Anatomy of the gastrointestinal system
What does the digestive system include?
It includes the digestive tract and its accessory organs, which process food into molecules that can be absorbed and utilized by the cells of the body.
What is the digestive tract called and what does it consists of?
It also called the alimentary canal or gastrointestinal (GI) tract, consists of a long continuous tube that extends from the mouth to the anus.
What does the digestive system make up of?
Includes the mouth, pharynx, esophagus, stomach, small intestine, and large intestine.
What are the major accessory organs in the digestive system?
Salivary glands, liver, gallbladder and pancreas
What does salivary glands do?
They produce saliva and they pour their
secretions into the oral cavity through the ducts.
what are salivary glands separated into?
they are divided into lobules
What are lobules in the salivary glands separated by?
Lobules are separated from one another by the connective tissue septa
What does lobules contain?
Contain secreting units called acini, ducts which drain the acini.
What is the acinus in the lobules of the salivary glands?
Acinus is an oval or spherical structure which has a lumen in the center and enclosed by a basement membrane.
What is between the basement membrane and the epithelial cells of the acini in the lobules of the salivary glands?
Myoepithelial cells lie between the epithelial cells and the basement membrane.
What does the myoepithelial cells do?
These cells squeeze out secretion.
What are the acini drained by?
Acini are drained by the intercalated ducts
What are the 3 types of acinus?
Mucous acinus, serous acinus, and mixed acinus
What is the shape of the mucous acinus? and what is it lined by?
Oval shaped structure, has a large lumen and it is Lined by columnar cells (acinar cells) Cells have flat nucleus situated on the basement membrane.
what does the mucous acinus contains in a fresh condition?
In the fresh condition they contain large secretory granules of mucinogen near the apex.
How does the mucous acinus looks on a slide?
The secretory product has either been dissolved during the staining process or remains unstained
• Due to this, the cells are clear and transparent
What is the shape of the serous acinus? and what is it lined by?
Spherical structure and smaller than mucous acinus Has a small lumen, lined by columnar or pyramidal cells. Cells contain a round nucleus which is placed near basal part.
How does the serous acinus looks on a slide?
In an H&E stain, the cytoplasm at the apical part of the cell appear pinkish The apical part contains
secretory granules.
What are mixed acinus?
These are the mucous acini .They have a half moon (crescent) shaped cap of serous cells on them.
What does the caps of serous cells in mixed acinus do?
These caps of serous cells attach to mucus producing acini and empty their secretory product into interstices between the mucus-producing cell.
what are the caps of serous cells called?
These caps of serous cells are called serous demilunes or crescents of Gianuzzi.
What are the 2 types of Intralobular ducts?
intercalated ducts and striated ducts
What does Intercalated ducts do?
drain the acini and lined by simple
cuboidal epithelium
How are striated ducts formed?
Striated ducts formed by the intercalated ducts and
lined by simple columnar epithelium
