Gastrointestinal Function Flashcards
What are the functions of the gastrointestinal tract?
Digestion Absorption Motility Excretion Secretion
Which cells produce digestive enzymes?
Absorptive cells
Which cells produce mucus?
Goblet cells
What cells are located at the base of the crypts?
Endocrine cells
Why are there plenty of stem cells at the base of the crypts?
To compensate for a high cellular turnover
Which vein do all GI veins drain into?
The hepatic portal vein
What is the benefit of all GI veins draining into one vein?
This vein passes through the liver which allows for detection of nutrient levels and detoxification of the blood
How is the GI tract regulated?
Paracrine, endocrine and neural signalling
What are the two plexuses within the enteric nervous system?
Myenteric and submucosal
What do the enteric plexuses modulate?
Smooth muscle contraction
Cellular secretion
Hormone secretion
Vasoconstriction and dilation
Which branch of the CNS increases digestion?
Parasympathetic
What special property is held by the interstitial cells of Cajal?
They have a pacemaker current which spontaneously activates smooth muscle
