Gi Large Intestine Flashcards
What is the Ileocecal sphincter
Maintain positive resting pressure (shut)
Relaxes in response ro distension. Of due
Contracts reoosne to distension of ascending colon to prevent backward flow of fractal matter
Under control vagal nerves, symp neve and enteric nerve s
What are the primary functions of the large intestine
Absorption
Secretion
Reservoir
Periodic elim of faeces
What does the large ins testing abs
Short chain fatty acids - carbs not abs they are fermented by colonic bac to short chain FA’s
ABs of water, sodium a nd chloride
What dos the large intestine secrete
Pottasium
Bicarbonate
Mucus
Convert liquid to semi solid faecal matter
How is the large intestine a reservoir
Storage of colonic matter
Where does the final drying stage occur
Descending and sigmoid
Where does most of the fluid reabs and bac fermentation occur
In ascending and transverse
What is haustration
Non propulsive segmentation
Caused by contraction of circular muscle
What is mass movement
Peristaltic contractions 1-3 times a day
Simultaneous. Not action of large segments of circular muscle of ascendin and transverse
What is mass movement triggered by
Gastrocolic repsonse involving
Gastrin
Extrinsic nerve plexuses
What does relaxation of skeletal muscle of external anal sphincter vol
Defaecation assisted by abdominal contraction increasing pressure squeezing large intestine and expiration against closed glottis further pressure
What kind of process is abs of water
Passive driven by solutes (water follow slat move)
How can water move
Trans cellular
Para cell
What do here large intestine consist of
Colon - ascending, transverse, descending, sigmoid
Caecum
Appendix
Rectum
