Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

GI Final > Secretions of the GI Tract and Panceas > Flashcards

Secretions of the GI Tract and Panceas Flashcards

(53 cards)

Start Studying
1
Q

functions of saliva

A

initial digestion of starches and lipids
dilution and buffering of ingested food
lubrication of ingested food with mucus

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

parotid glands

A

largest of the salivary structure
located near the angle of the jaw and the ear
composed of serous cells
secrete fluids composed of water, ions, and enzymes (rich in amylase)
secrete 25% of the daily output of saliva

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

submaxillary glands and sublingual glands

A

composed of serous and mucous cells
secrete aqueous fluid and mucin glycoprotein for lubrication
secrete most of the rest of 75% of daily output saliva

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

salivary galnd

A

ectodermal in origin
has the appearance of a bunch of grapes
similar features as the exocrine pancreas
the blood supplied to the salivary glands is distributed by carotid artery

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

acinus - blind end

A

acinar cells secrete initial saliva

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

myoepithelial cells

A

rest on the basement membrane of acinar cells
contain an actinomycin
have motile extensions
when stimulated by neural input, contract to eject saliva into the mouth

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

intercalated duct

A

contains myoepithelial cells

saliva in the intercalated duct is similar in ionic composition to plasma

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

striated duct

A

lined by columnar epithelial cells (ductal cells)
ductal cells modify the initial saliva to produce the final saliva (hypotonic)
ductal cells alter the concentration of various electrolytes

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

composition of saliva

A

water, electrolytes, alpha amylase, lingual lipase, killikrein, and mucose
increased K and HCO3
decreased N and Cl

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

alpha amylase

A

begins initial digestion of carbohydrates

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

lingual lipase

A

beings initial digestion of lipids

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

killikrein

A

protease involved in the production of bradykinin (vasodilator)

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

mechanism of salivary secretion

A

formation of isotonic plasma like solution by acinar cells

modification of the isotonic solution by the ductal cells

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

cystic fibrosis

A

pt. lack the Cl transporter

salivary Ca Na and protein are elevated

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

flow rate and ion composition of saliva

A

increased - saliva resembles plasma and initial saliva

decreased - saliva has lower concentrations of Na and Cl and higher K

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

parasympathetic inn of salivary glands

A

presynaptic n originate at facial and glossopharyngeal n

postsynaptic fibers in autonomic ganglia innervate individual glands

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

sympathetic inn of salivary glands

A

preganglionic n originate at the cervical ganglion

postganglionic fibers extend to the glands in the periarterial spaces

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

HCl

A

with peptin will initiate the process of protein digestion
needed for the conversion of pepsinogen to the enxyme pepsin
kills a large number of bacteria that enter the stomach

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

pepsinogen

A

inactive precursor to peptin

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

mucus

A

lines the wall of the stomach and protects it from damage
acts as lubricant
together with HCO neutralized acid and maintains the surface of the mucosa at a neural pH

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

intrinsic factor

A

required for the absorption of vit B12 in the ileum

indispensable component

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

water

Study These Flashcards
A

medium for the action of HCl and enzymes

solubilizes much of the ingested material

23
Q

ocyntic gland

Study These Flashcards
A

located in the proximal 80% of the stomach (body and fundus)
secretes acid

24
Q

pyloric gland

Study These Flashcards
A

located in the distal 20% of the stomach (antrum)

synthesizes and release gastrin

25
parietal cells
intrinsic factor and HCl
26
chief cells
pepsinogen
27
G cells
gastrin
28
mucus cells
mucus, HCO3, and pepsinogen
29
histamine regulation of HCl
stimulation of HCl secretion released form ECL cells binds to H2 R on parietal cells leads to cAMP which will activate H/K ATPase
30
Ach regulation of HCl
stimulation of HCl secretion released from vagus n binds to M3 mAChR on parietal cells leads to IP3 and Ca2 release which stimulates H/K ATPase stimulation of ECL cells
31
gastrin regulation of HCl
stimulates HCl secretion secreted by G cells binds to CCKB R on parietal cells leads to IP3 and Ca2 leading to stimulation of H/K ATPase stimulation of ECL cells
32
somatostatin regulation of HCl
inhibits HCL secretion secreted by detla cells binds to SSTR2 R on parietal cells which inhibits adenylate cyclase inhibits histamine and gastrin
33
vagus n and HCl secretion
direct pathway - stimulation of parietal cells | indirect pathway - stimulation of G cells
34
cephalic phase
30% of HCl secreted in response to meal brain tells stomach to prepare for receipt of meal vagus n. - fxn through direct and indirect pathways to lead to release of HCl
35
gastric phase
60% of the total HCl secreted in response to meal distention of the stomach and presence of breakdown of proteins, amino acids, and small peptides activation of mechanoR leads to stimulation of the vagus n, local stimulation of G cells
36
intestine phase
less than 10% of the total HCl secreted in response to meal distention of SI stimulates acid secretion digested protein stimulate acid secretion via direct effect on parietal cells through gastrin relase
37
gastric juice secretion rate
low - solution of NaCl high - more H than Na more H, K , and Cl and less Na than plasma
38
non parietal gastric secretion
basal alkaline secretion of constant and low volume make of Na, Cl, and K at same concentration as K HCO3is secreted at a concentration of 30 mEq/L
39
parietal gastric secretion
hyperosmotic 150-160 mEq H/L and 10-20 mEq/L Cl is the only anion present as secretion rate increases the concentration of electrolytes begin to approach those of pure parietal cell secretion
40
regulation of gastrin release
stimulated by GRP which is released though stimulation of vagus n inhibited by somatostatin works through negative feedback
41
pepsinogen secretion
secreted by chief cells and mucus cells in the oxyntic glands needs to be converted into pepsin by H vagus n stimulation is the most important stimulus for pepsinogen secretion H will trigger the release of pepsinogen
42
function of pepsin
``` converts more pepsinogen to pepsin splits interior peptide linkages pH 1.8 to 3.5 reversible inactivated at pH greater than 5 irreversible inactivated at pH 7-8 ```
43
intrinsic factor
secreted by parietal cells combines with B12 to make a complex which allows the absorption of B12 no secretion leads to pernicious anemia
44
growth of gastic mucosa
epithelium secretes HCO3 and mucus to form gel like mucosal barrier (neck cells - mucus and epithelial cells - HCO3) protects the gastric mucosal epithelium against HCl and pepsin
45
factors that protect gastric mucosa
HCO3, mucus, prostaglandins, mucosal blood flow and GF
46
factors that damage gastric mucosa
acid, pepsin, NSAIDs, H pylori, aspirin, bile and stress
47
peptic ulcer diseases
H. pylori infections and NSAID use | loss of protective mucosal barrier, excessive H and pepsin secretion
48
gastric ulcers
because of mucosal barrier defect caused by H. pylori urease converts urea to NH3 which alkalinizes the local environment which lets the bacteria live
49
duodenal ulcers
H secretory rates are higher than normal | H. pylori inhibits somatostatin
50
zollinger-ellison syndrome
duodenal ulcers | tumor in the panceas secretes large quantities of gastrin
51
exocrine panceas
secretes aqueous solution containing HCO3 and enzymatic secretion acinus - secrete enzymatic portion ducts - secrete HCO3
52
inn of exocrine pancreas
sympathetic- celiac and superior mesenteric plexuses (inhibit) parasympathetic - vagus n (activates)
53
secretion rate of pancreatic juices
increased - high HCO3 and Cl lowest | decreased - high Cl and HCO3 lowest

GI Final (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions