Lp 39

Question 1

-thick walled & muscular
-highly specialized mucosa
-length 15-25cm
-volume 39ml-4l
-regions:
*cardia: superior area
*fundus: area inferior to diaphragm
*body: mid-portion
*pylordus: distal area

Answer 1

Stomach structures

Question 2

3 layers in muscularis

Answer 2

-outer: longitudinal
-middle: circular
-inner: oblique

Question 3

-cardiac (aka LES or GES): prevents back flow into esophagus
Pyloric controls emptying into SI

Answer 3

2 sphincters

Question 4

2 curvatures

Answer 4

-greater (lateral)
-lesser (medial)

Question 5

2 mesenteries (aka omenta)

Answer 5

-extend from curvatures
-anchor stomach

Question 6

Exocrine glands

Answer 6

Ducts carry secretions not stomach cavity

Question 7

Endocrine glands

Answer 7

Ductless, hormones excreted into blood

Question 8

Contains:
-mucous surface cells: secrete mucus
-mucous neck cells: secrete mucus
-parietal cells: secrete HCI & intrinsic factor (for vit.b12 absorption)
-chief cells: secrete digestive enzymes

Answer 8

Exocrine glands

Question 9

Contains:
G cells (enteroendocrine cells): secrete gastriN

Answer 9

Endocrine glands

Question 10

-2-3L daily: produced & secreted by chief cells, neck cells & parietal cells
-cells line & release secretions into gastric pits-mix & pour into stomach lumen

Answer 10

Gastric juice

Question 11

-gastric mucosa- resistant to acid d/t impermeability to H+
-substances that decrease mucosal barrier & allow H+ to damage mucosa: aspirin, alcohol, bile
-decrease in cell pH leads to denatured proteins & decrease cell Fxn

Answer 11

Hydrocholoric acid

Question 12

3 sites /phases to gastric regulation

Answer 12

-head: cephalic phase
-stomach: gastric phase
-SI: intestinal phase

Question 13

-sight, smell & thought of old increase brain activity
-cortex & hypothalamus send signals to vagaries nuchlei (medulla)
-vagus n increase gastric activity
-gastric secretions increase
-digestion in stomach increase
-phase prepares stomach for digestion

Answer 13

Cephalic phase

Question 14

-d/t food in stomach
-stomach distension activates:
*vagovagal reflex (long)
*local reflexes (short)
*both increases gastric sensation
-increase gastriN secretion d/t:
*low acidity (decrease HCI)
*proteins, peptides, caffeine
-gastrin increases secretion of acid & enzymes for protein digestion

Answer 14

Gastric phase

Question 15

Factors that activate gastrin secretion

Answer 15

-emotional upset
-fear
-anxiety
-stress

Question 16

2 components:
-increase gastric secretion (brief)
*when stomach begins to empty into duodenum
*keeps stomach contents moving
-decreases gastric secretion
*as chyme empties into duodenum

Answer 16

Intestinal phase