ch 23 digestive system p2 Flashcards

1
Q

cardia of stomach

A

portion leading right out of the esophagus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

fundus of stomach

A

dome shaped portion of stomach on top

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

body of stomach

A

midportion of stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

pyloric portion of stomach

A

inferior funnel shaped portion of stomach, leads right into small intestine, has the pyloric sphincter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

pyloric sphincter

A

thick tissue controls release of food from stomach to intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

omenta

A

mesenteries extending from greater and lesser curvature of stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

lesser vs greater omentum

A

lesser is from liver to stomach and greater is stomach to intestines (its like a purse to hold intestines and spleen with many lymph nodes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

the autonomic innervation of stomach, parasympathetic vs symp

A

parasympathetic- via vagus nerve, increase digestion and muslce walls contract for rest and digest
sympathetic- decrease digestion, less stomach activity bc fight or flight thoracic splanchic nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

stomach has 3 layers of muscle what n why

A

circular, longitudinal, oblique, allows each organ to have their own function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

oblique muscle layer

A

provides extra muscle layer to generate force. stomach twists like a towel, shortens and widens. helps break down food by churning literally, moves the food and pummels Into smaller pieces to increase SA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

mucosa of stomach has what

A

surface epithelia, simple columnar cells that secrete a lot of mucous with a basic pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

lining of the mucosa has what

A

gastric pits, which leads to gastric glands and secretes gastric juices.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

mucous neck cell stomach

A

produces acidic and thin mucus, may protect other cells bc its more acidic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

parietal cells stomach

A

secretes HCl and intrinsic factor
HCl makes it really acidic! 1.5-3.5
activates protein digestive pepsin which breaks down the plant cell walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

pepsin

A

breaks down plant cell walls and kills bacteria, activated with HCl starts the proteins digestion which denatures protein!!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

intrinsic factor stomach

A

necessary for vitamin B12 absorption in small intestine. B12 is a coenzyme for manny reactions such as ATP. also for erythropoiesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

chief cells stomach

A

produces pepsinogen, which is converted to pepsin, which as we know starts protein digestion in stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

enteroendocrine cells of stomach

A

releases hormones, histamine and serotonin and somatostatin and gastrin!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

histamine from enteroendocrine cells

A

stimulates parietal cells to release HCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

serotonin from enteroendocrine cells

A

stimulates contraction of muscle in stomach wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

somatostatin from enteroendocrine cells

A

slows gastric function, plays several inhibitory roles in stomach and other organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

gastrin from enteroendocrine cells

A

increases HCl secretion, stimulates contraction. of intestinal muscle, releases ileocecal valve, stimulates mass movement of materials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

mucosal barrier of the stomach

A

protects stomach from its own gastric juice, bc low pH would corrode the stomach itself

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

the 3 mechanisms of protection for the stomach

A

thick alkaline mucus on internal surface of stomach (physical barrier), epithelial cells joined by tight junctions (ensures gastric juices can’t leave stomach), damaged epithelial cells are replaced fast (undifferentiated stem cells in gastric pits replace damaged cells, mitosis ensures that protection)

25
smooth muslce is thickest where
bottom of the stomach, the strongest contractions occur here for greater mixing and churning
26
retropulsion
as food is mixed and churned in the pylorus, small liquid and food particles can pass through pyloric valve, making chyme that will die (some of it) and not pass through pyloric valve.
27
chyme
gastric juice and partially digested food together that will remain in stomach until gets smaller or die
28
how is the rate of contraction established in the stomach
enteric pacemaker cells, very slow, APs are sent to smooth muslce cells slowly. NOT FORCE OF CONTRACTION
29
what determines force of contraction of the stomach muscle
intiric pacemaker cells
30
what does the rate of emptying stomach depend on
S/L in the stomach L is faster in digestion, how distended is the stomach (stronger contractions is more chyme to small intestine), contents of 1st part of small intestine
31
contents of 1st part of small intestine regulating stomach emptying
duodenum receptors react to food, suppress gastric secretions to slow gastric emptying. ensure small intestine has good chyme. suppresses pyloric contractions in stomach and slows it down, fatty chyme makes fat take more time to digest than carbs
32
liver
accessory to small intestine, has 4 lobes (right left caudate and quadrate)
33
falciform ligament of liver
divides L from R, suspends liver from diaphragm, prevents movement
34
round ligament of liver
remnant of umbilical vein its always there q
35
how do liver products drain from lobes
common hepatic ducts, bile from liver drains
36
is the liver hollow
no, has liver lobules densely packed with hepatocytes
37
hepatocytes functions
many functions, bile secretions and process blood borne nutrients, stores fat soluble vitamins and detoxifies blood.
38
only organ that regenerates
liver!
39
each corner of lobule has portal triad, which has. a
hepatic artery branch, hepatic portal brach, and bile duct.
40
liver sinusoids
drain blood from portal triad, empties into central vein.
41
what happens to blood traveling through liver sinusoids
blood gets cleansed by sinusoid capillaries, hepatocytes clean it up!
42
bile canaliculi
drain bile secreted by hepatocytes and enters bile duct of portal triad, then drained into duodenum
43
function of central vein that runs through the center of each lobule
takes blood ad brings it to hepatic vein for general circulation where it can be exposed to other organs
44
blood vs bile where does it travel q
blood from portal triad to center, bile from portal triad to be dumped
45
bile is
yellow green alkaline solution produced by hepatocytes
46
bile components
bile salts and bilirubin
47
bile salts from bile
component of bile aids in digestion n absorbs fats. does the digestive function. bile salts never leave body just get recycled and saves energy so we don't need to produce more bile
48
bilirubin
bile pigment formed by heme breakdown, absorbed from blood in liver, excreted into bile, metabolized in small intestine by bacteria.
49
bilirubin circulation
circulates until liver, dumps bilirubin to bile, then removes via solid waste
50
gallbladder
accessory organ to liver and small intestine. helps digest fats bc liver stores bile in the gallbladder. inferior surface and green in color, absorbs water and ions from bile.
51
how does gallbladder empty bile
via cystic duct into common bile duct then small intestine.
52
gall stones
crystallized bile salts, painful af
53
pancrea
accessory to small intestine, secretes substances that help digest wide variety of foodstuff.
54
exocrine part of pancreas
secretes pancreatic juce, has acini- synthesized and stores digestive enzymes, as well as secreting them. ducts- transports acini secretions
55
why is it necessary to have inactive digestive enzymes in the exorcrin pancreas
if they were active, pancreas would digest itself. only active with low pH chyme.
56
endocrine part of pancreas
contains pancreatic islets, has alpha cells and beta cells
57
alpha vs beta cells in endocrine part of pancreas
alpha- secretes glucagon to increase blood glucose levels (hyperglycemic) beta- secretes insulin to decrease blood glucose levels (hypoglycemia)
58
composition of pancreatic juice
water, enzymes, and electrolytes, alkaline in nature.
59
how is the pH of pancreatic juices important to the small intestine.
pH neutralizes chyme, so pancreatic enzymes can digest protein n fats n carbs