Small Intestine Flashcards
What does the villus cell of the small intestine absorb?
NaCl Monosaccharides Amino acids Peptides Fats Vitamins Minerals Water
What do the crypts cells of the small intestine secrete?
Water and chloride
Which layer of muscularis externa is incomplete in the large bowel?
Longitudinal-three bands form the teniae coli which then produce haustra from the large intestine
What is the mucosa of the anal sphincter and rectum?
Anal sphincter-simple columnar
Rectum-stratified squamous
What is the main function of the large intestine?
To reabsorb water from the chyme
What are the contractions of the large intestine called?
Mass movement which precipitates defecation
What vitamin do colonic bacteria produce?
Vit K
What control is the defecation reflex under?
Parasympathetic control via the pelvic splanchnic nerves
What is given as a treatment for diarrhoea and why does it work?
Sodium/glucose solution
Works by osmotically driving water back into the body.
What are two enterotoxigenic bacteria that cause diarrhoea?
Vibrio cholerae
Escherichia coli
How do enterotoxigenic bacteria cause diarrhoea?
They produce toxins that turn on chloride channels to maximum so water is secreted. The villi are swamped so also can’t reabsorb. Acts as a protective measure to try to flush bacteria out but ultimately can lead to dehydration.
