Physio- Colon Flashcards
What are the 2 main movements of the colon?
Haustrations and mass movements
What happens to poop when Haustrations happen?
It’s mixed (it’s like segmentation of the SI)
What happens to poop when mass movements occur?
It’s moved forward through the colon (like peristalsis in the GI)
Which 2 intestinal reflexes increases mass movements in the colon?
Gastrocolic and duodenocolic
When poop causes stretching of the rectum, which sphicter is relaxed? Internal or external?
Internal anal sphincter
So how do you get poop out from your rectum?
Relaxation of the external anal sphincter
True or False: the defectation reflex is strong by having the myenteric reflex have mass movements in the colon.
False, you need PANS from the sacral spinal cord to have a good bowel movement.
Is the external anal sphincter composed of voluntary striated muscle or involuntary smooth muscle?
Strated muscle! Rememebr this is the 1 u voluntarily relax when you’re ready to poop.
Which nerve innervates the external anal sphincter?
Pedendal n.
The crypts pof Lieberkuhn secrete what substances in the colon?
Mucus and some bicarb
What determines the rate of mucus production fotkm the crypts of Lieberkuhn in the colon?
tactily stimulation of the epithelial cells in the colon and by local nerve reflexes.
What happens if the colon is irritated?
The body secretes a large amt of water/electrolytes/mucus –> diarrhea
The colon is a large place for the absorption of what substance?
Water
First, the colon must absorb what substance in order to absorb water?
NaCl
The over-absorbtion of fluid in the gut can cause what complaint?
Constipation
What is the other cause of constipation (think tumors and adhesions and ulcers)?
Obstructions
Why can constipation occur later in life if kids don’t develop good bowel habits?
Progressive decrease of reflex strength
This is the cause of diarrhea when irritation from infection causes extensive secretion and increased motility in order order to propel the irritant.
Enteritis
This type of diarrhea is from the triggering by nervousness causing excess stimulation of the PANS.
Psychogenic diarrhea
This conditions is when the walls of the colon are inflammed and ulcerated, causing excess secretions and mass movements throughout the day.
Ulcerative colitis
What is flatus?
Fart
What are the 3 sources of farts?
- swallowed gas. 2. bacterial products. 3. gases from the blood.
