Large Intestine Flashcards
What are the sections of the large intestine
Caecum
Colon
Rectum
What are the sections of the colon
Ascending
Transverse
Descending
Sigmoid
What is the ileo-caecal junction
Junction between caecum and ascending colon
Fold of mucosa allows chyme to pass from small intestine to large but not vice versa
What epithelium is found in the large intestine
Simple columnar with goblet cells
What type of glands are present in the large intestine
Mucosal glands (mucous)
Differences between small and large intestine
Large Intestine has:
No villi
Incomplete layer of longitudinal muscle - taenia coil
Ring like arrangement of circular muscle - haustrae
What are properties of the recto-anal junction
Quick change in epithelium from simple columnar to the skin
Prone to cancer
What is known as the failure to reabsorbed fluid
Diarrhoea
What is the function of intestinal flora
Ferment dietary fibre (cellulose) and lipid
Produces gases
Synthesises vitamins B and K
What are mass movements
Infrequent, sustained contractions usually after meals
Moves chyme/faeces from proximal colon to distal colon
What is defaecation
Ejection of faecal matter from anal canal
What type of muscle is found in the rectum
Internal anal sphincter is smooth muscle controlled by the ANS
External sphincter is striated skeletal muscle
Voluntary control is gained at around the age of 2
What is a colostomy
Disease of the large intestine resulting in removal of a section of the colon
The ileum or colon is brought out through the abdominal wall
The opening is called a stoma and faecal matter is collected in a bag
What does diarrhoea result in
Dehydration and electrolyte imbalance
What is constipation
Hard faeces that is difficult to pass
Due to increased fluid absorption
Side effects of the drugs opiates
What is the function of the colon
Absorbs fluid and electrolytes from small intestine chyme
Describe the caecum
Sac like structure that receives contents of the ileum and continues the absorption of water and salts
What is the appendix
Windy tube that attaches to the caecum
No function
What is haustra
Due to ring like arrangement of circular muscle
Pulls in at one place
What is teniae coli
3 bands of smooth muscle that make up the longitudinal muscle layer of the muscularis of the large intestine
What are the sphincters of the anal canal
Internal and external
Describe the internal anal sphincter
Made up of smooth muscle so contractions are involuntary
Describe the external anal sphincter
Made up of skeletal muscle which is under voluntary control
What is the definition of diarrhoea
Going to the toilet more than 3 times a day
