Digestive System

Question 1

Tight junctions

Answer 1

a barrier that separates body fluids from extracellular environment

Question 2

Functional syncytium

Answer 2

one cell has an action potential and contracts -> impulse spreads to neighboring cells

Question 3

GI smooth muscle exhibits automacity =?

Answer 3

contracts periodically w/o external stimulation due to spontaneous depolarization

Question 4

Myenteric Plexus

Answer 4

found between circular and longitudinal muscle layers

helps regulate gut motility

Question 5

Submucosal Plexus

Answer 5

submucosa layer
helps regulate enzyme secretion, gut blood flow, ion/water balance in the lumen
sparse in esophagus, anus

Question 6

Layers of the GI tract

Answer 6

lumen -> mucosa -> submucosa -> circular muscularis -> longitudinal muscularis -> serosa

Question 7

Mucosa

Answer 7

villi

epithelial tissue

Question 8

Submucosa

Answer 8

connective tissue

Question 9

Circular/longitudinal Muscularis

Answer 9

smooth muscle

Question 10

Serosa

Answer 10

connective tissue

Question 11

Acinar cells

Answer 11

secrete products which pass into ducts

exocrine

Question 12

Mouth roles in digestion:

Answer 12

1. fragmentation
2. lubrication
3. some enzyme digestion
   - ptyalin -> smallest = disaccharide
   - lingual lipase = fat digestion

Question 13

Beta oxidation # of cycles =

Answer 13

n/2 -1