HISTOLOGY GI TRACT
What are the glands of the stomach and their functions?
1) Parietal (Oxnitic)- secrete HCL and intrinsic factor 2) Chief cells- secrete pepsinogen, rennin, lipase
How is the appendix recognized?
Flat on the surface, straight glands, and giant lymph nodes.
The mucosa of the esophagus is what kind of tissue?
Flat squamous- stratified squamous non-kertinized
What is the defining characteristic of the colon?
Flat surface (no villi) Straight glands lots of goblet cells!
Mucosa of the stomach is what?
Flat, tortuous glands
The mucosa of the colon is what?
Flat- straight glands
What cells can you see in the small bowel?
In the crypts of lieberkun Absorptive cell Goblet cell Paneth cell
The jejunum contains what kind of mucosa?
Jejunum- standard villi, NO glands
Change in structure from Pylorus to Duodenum:
Lymph- stomach Villi and Brunner's glands- Dueodenum
What is the general layout of the gut by layers?
Mucosa Muscularis Mucosa Submucosa 2 layers of muscle (inner-circular, outer-longitudanal) Autonomic Ganglia Serosa or Adventitia
What kind of glands are in the Pyloric (Antral) mucosa?
Mucous cells (mucous and lysozyme) and Neuroendocrine cells (Gastrin- primary site)
What kind of glands in the esophagous?
Mucous, pepsinogen, lysozyme
How do you recognize Goblet cells?
Pale because of mucous
What kind of cells are Paneth cells? What do they contain?
Paneth cells- granular cells with lysozyme
What do parietal cells look like? Chief cells?
Parietal- slightly more pale Chief cells- darker, granulated
What is the defining characteristic of the ileum?
Peyers patches, and numerous lymph follicles
What kind of cells in the proximal part of the anal canal?
Simple columnar Lots of nerve endings in the ass- distinguish between solid, liquid, gas.
When is the first time you see goblet cells in the gut?
Small bowel- first part of duodenum They secrete alkaline mucous that neutralizes stomach acid. Also produce urogastrone that inhibits HCL production.
What's inside the villus core of the small intestines?
Smooth muscle, lacteals, and plasma cells. 250 square meters
In the stomach, there are more folds.
Surface lining cells Mucuous neck cells Parietal cells (HCL) Chief Cells (Zymogenic) Enteroendocrine cells
What kind of muscle in the esophagus muscularis externa?
Upper 1/3- Skeletal Middle 1/3-Mixed Lower 1/3- smooth
The mucosa of the small intestine is what?
Villous
What kind of cells in the distal anal canal?
Distal- stratified squamous mucosal
Duodenum contains ______ glands
Duodenum- submucosal/Brunner's glands
