Stomach Flashcards
Where is the stomach?
between the duodenum and oesophagus
Where is the stomach found in the abdominal regions?
epigastric, left hypochondrium
What is at the anterior/superior regions of the stomach?
lower ribs/ diaphragm
liver
What is at the posterior/inferior regions of the stomach?
diaphragm, spleen, left kidney, adrenal gland, pancreas
What does the pyloric sphincter do?
allows food to pass from the stomach to the small intestine -prevents partially digested food and digestive juices from reentering the stomach
What condition can affect the pyloric sphincter?
pyloric stenosis which prevents the stomach from emptying into the small intestine
What are the rugae?
folds of the organ which can be seen with the naked eye. They help increase surface area and allow for the folding and expansion of the organ.
What are the 3 muscles of the stomach
inner circular
outer longitudinal
an extra layer called the innermost oblique.
What substances does the stomach absorb and what is this due to?
aspirin and alcohol due to high vascularisation
What are the secretory cells of the stomach and what do they secret?
mucous cells - mucus
parietal (oxyntic) cells - HCL and intrinsic factor
chief (zymogenic) cells - pepsinogen, lipase
neuroendocrine cells (G cells) - gastrin, serotonin
What is the difference between the neck mucous cells and the surface mucous cells?
neck cells produce mucus that is a little more acidic
What is the intrinsic factor required for?
Vitamin B12 absorption in the ileum
What happens to pepsinogen?
becomes activated by HCL breaking it down to become pepsin which breaks proteins into smaller amino acids
What stimulates the production of HCL by parietal cells?
hormone gastrin released in the bloodstream by endocrine cells stimulates parietal cells to produce HCL
Describe parietal (oxyntic) cells in an H&E stain
large round or pyramid-shaped cells, highly acidophilic (very pink), central round nucleus
Describe chief (zymogenic) cells in an H&E stain
found in lower regions of the gastric glands, basophilic (very blue)