GI Part 3- 1 Flashcards
What surface convolutions of the small intestine has the largest surface area?
Microvilli
What are the base of the vili that acts are gland-like structures called?
Crypts of Lieberkuhn
What are located in the small intestine:
Tubule alveolar glands
Secretion of mucus through exocytosis
Secrete glycoproteins and bicarbonate ions
Brunners glands
What has the function of protecting the small intestine mucosa by neutralizing the acid containing chyme delivered to it from the stomach?
Brunners glands
Where does the division and replication of enterocytes ONLY occur at?
Crypts
What are the most rapidly regenerating cells of the body?
Intestinal crypt cells
What is the turnover time of enterocytes?
4-7 days
What cells arise from the stem cell compartment and differentiate into absorptive enterocytes or secretory goblet, enteroendocrine, or paneth cells?
Progenitor cells
Do paneth cells move downward or upward into the crypt?
Downward into the base columnar cells
Water moves in any direction to keep ingesta ___________
Isoosmotic
What has the following:
Microbial metabolism
One layer cylindric epithel water absorption, vitamins
Goblet cells —> mucus
Secretes: small volume isoton to plasma, mucin, bicarbonate and potassium rich
Large intestine
What do the cecum and colon not have?
Vili
Where does water and nutrients enter first before entering the vascular system?
Extracellular fluid
What 2 forces drives the movement of solutes and water between intravascular and extravascular fluids?
Osmotic and hydrostatic forces
Absorbed nutrients enters the __________ by diffusion from the interstitium
Capillaries