Summary
Summary chapter 15 GI system Junqueira's Basic Histology
- Course
- Institution
- Book
chapter 15 GI system Junqueira's Basic Histology
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
Summary endocrinology (NWI-BB048B)
-
chapter 14 histology Junqueira's Basic Histology
-
chapter 16 Gi Junqueira's Basic Histology summary
1 review
By: rayyanramzan2004 • 4 months ago
Seller
Follow
OGN
Reviews received
Content preview
Digestive System Digestive system consists of the digestive (GI) tract or alimentary canal, oral cavity, esophagus, stomach, small and
large intestines, and anus—and its associated glands—salivary glands, liver, and pancreas
Its function is to obtain from ingested food the molecules necessary for the maintenance, growth, and energy needs
of the body.
1. Structures within the digestive tract allow the following (functions)
2. Ingestion, or introduction of food and liquid into the oral cavity.
3. Mastication, or chewing, which divides solid food into digestible pieces.
4. Motility, muscular movements of materials through the tract.
5. Secretion of lubricating and protective mucus, digestive enzymes, acidic and alkaline fluids, and bile.
6. Hormone release for local control of motility and secretion.
7. Chemical digestion or enzymatic degradation of large macromolecules to smaller ones and their subunits.
8. Absorption of the small molecules and water into the blood and lymph.
9. Elimination of indigestible, unabsorbed components of food.
General structure of GI tract (4 main layers):
o Mucosa (mucous membrane):
Epithelial lining
Lamina propria of loose connective tissue rich in blood vessels, lymphatics, lymphocytes, smooth muscle cells, and
often small glands.
Muscularis mucosae which is smooth muscle separating mucosa from submucosa.
o Submucosa:
Has denser connective tissue with larger blood and lymph vessels
Has submucosal (Meissner) plexus of autonomic nerves.
Might contain glands and lymphoid tissue.
o Muscularis Externa:
2 or more layers of smooth muscle
A. Internal one is usually circular
B. External one is usually longitudinal
Connective tissue between muscle layers has blood and lymph vessels, and myenteric (Auerbach) nerve plexus of
many autonomic neurons.
A. This plexus with the submucosal plexus form the enteric nervous system of the digestive tract.
o This system contracts the smooth muscles to propel luminal contents forward.
, o Serosa:
Thin layer of loose connective tissue rich in blood vessels, lymphatics, and adipose tissue with mesothelium.
In abdominal cavity, it is continuous with mesenteries (both sides of intestines)
A. Mesenteries are continuous with the peritoneum, a serous membrane that lines that cavity
NOTE: In places where the digestive tract is not suspended in a cavity but bound to adjacent structures (esophagus),
serosa is replaced by a thick adventitia (a connective tissue that merges with the surrounding tissues and lacks
mesothelium)
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller OGN. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79373 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now