Histology of Stomach and small intestines Flashcards
Loubi
List the tissular organization of the digest system starting from the innermost layer
Mucosa
Submucosa
Muscularis Externa
Serousa
What kind of tissue is the submucosa made up of
Dense irregular connective tissue
What controls motricity of mucosa and secretory activity of mucosal gland in the submucosa
Meissner’s plexus(parasympathetic neurons)
Which 2 muscles comprises the muscularis externa
Circular smooth muscle( inner layer)
Outer Longitudinal smooth muscle
Which plexus is present between the circular and longitudinal layer of the muscularis externa
Myenteric ( Auerbach’s) Plexus
What type of fibres does the Auerbach’s plexus contain
Parasympathetic fibers
What kind of tissue makes up the Serosa of the digestive tract
Loose connective tissue- surrounding visceral organs
What kind of enzymes does the stomach secrete
Protein-digesting enzymes called Proteases
Name the four sections of the stomach and their functions
Cardia- Where the contents of the esophagus empty into the stomach
Fundus- Formed by the upper curvature of the organ
Body or Corpus- The main central region
Pylorus- The lower section of the organ that facilitates emptying the contents into the small intestines
What is the epithelium of the stomach
Simple columnar epithelium
What is the epithelium of the oesophagus
Stratified squamous epithelium
Define Rugae:
Longitudinal folds of mucosa and submucosa
note : all stomach regions have rugae
Rugae are temporary and disappear when stomach distended with fluid or solid material; True or FALSE
True
The stomach only has 3 histological regions name them:
Fundus and body
Cardia
Pylorus
Which region of the stomach are gastric glands located:
Fundus and body
There are 2 main cell types in the gastric glands located in the lamina propria of the mucosal layer; name them
Acidophilic parietal cells: in upper portions of glands
Basophilic Chief( zygomatic) cells- Lower portion of the glands
There are 3 layers of smooth muscle located in the Muscularis externa of the stomach; name them:
Inner oblique(not complete)
Middle circular
Outer Longitudinal
Describe the 3 regions of the gastric glands
Isthmus- junction of gastric pit with gastric gland; composed of acidophillic parietal cells
Neck- parietal cells
Base (fundus)- composed of chief (zymogenic cells), basophilic
3 Main types of cells in glands
Mucous neck cells: Round, basal nuclei
Parietal cells: large, pyramidal shape, round nuclei, acidophilic cytoplasm
Chief (zymogenic) cells: basophillic
What so parietal cells secrete
Intrinsic factor and HCL
Chief cells secrete
Pepsinogen and gastric lipase
What are G cells
Enteroendocrine cells that secrete gastrin into the blood