GIT Flashcards
What cells produce cholecystokinin ?
Gut endocrine cells (I cells) of the mucosa of the small intestine
What hormone is stimulated by fat in small intestine?
Cholecystokinin
In the stomach what release pepsinogen?
Chief cells
What activates pepsinogen?
- Acidic pH
2. Pepsin
What is pepsinogen?
An inactive pre cursor of the proteolytic enzyme pepsin
The breakdown of complex food stuff is accomplished by?
Hydrolysis
Complex starches are mainly digested by enzymes secreted from?
Pancreas (alpha amylase)
Which process transports AA across the luminal surface of the epithelium that lines the small intestine?
Co transport with NA ion
How does the stomach not digest itself?
- Gastric mucosal cells transport H ions out of gastric mucosa
- Pepsin is stored as pepsinogen so it will only be released when needed and does not digest the bodies own protein in stomach lining
How is stored fat usually transported from 1 side of the body to the other?
Free fatty acids
What is the concentration of free fatty acids in plasma?
15mg/dl
What is an essential AA?
An amino acid that cannot be synthesised de novo and must therefore be supplied by the diet
What are the 9 essential AA?
- Histidine
- Isoleucine
- Lysine
- Leucine
- methionine
- Phenylalanine
- Threonine
- Tryptophan
- Valine
What are the conditionally essential amino acids?
- Arginine
- Cystine
- Glycine
- Tyrosine
What is the meaning of a conditionally essential amino acid?
Not normally require in the diet but must be supplied exogenously to specific populations that do not synthesise adequate amounts