Digestive System Flashcards
(493 cards)
1
Q
What is the primary function of the digestive system?
A
To break down food into nutrients for absorption and eliminate waste.
2
Q
What is the difference between mechanical and chemical digestion?
A
Mechanical digestion involves physical breakdown (e.g., chewing), while chemical digestion involves enzymatic breakdown.
3
Q
What structures comprise the alimentary canal?
A
Oral cavity, esophagus, stomach, small intestine, large intestine, anus.
4
Q
What are the associated digestive organs?
A
Teeth, tongue, salivary glands, pancreas, liver, gallbladder.
5
Q
What are the three layers of the mucosa in the digestive tract?
A
Epithelium, lamina propria, muscularis mucosae.
6
Q
What are the two types of epithelium found in the digestive system?
A
Stratified squamous (protective regions) and simple columnar (absorptive/secreting regions).
7
Q
What are the four major layers of the gastrointestinal tract?
A
Mucosa, submucosa, muscularis externa, serosa/adventitia.
8
Q
How does the muscularis externa differ in different digestive organs?
A
It consists of smooth muscle but has striated muscle in the esophagus and anal canal.
9
Q
What role does the submucosal plexus (Meissner’s plexus) play?
A
Regulates secretion and blood flow in the GI tract.
10
Q
What is the function of the myenteric plexus (Auerbach’s plexus)?
A
Controls peristalsis and muscular contractions of the gut.
11
Q
Which organ secretes bile and what is its function?
A
The liver secretes bile, which emulsifies fats for digestion.
12
Q
What is the primary function of the esophagus?
A
To transport food from the oral cavity to the stomach.
13
Q
How does the stomach facilitate digestion?
A
Through mechanical churning, acid secretion, and enzymatic breakdown of proteins.
14
Q
Which hormone stimulates acid secretion in the stomach?
A
Gastrin, released by enteroendocrine cells in the stomach.
15
Q
What prevents the stomach from digesting itself?
A
A mucus layer rich in bicarbonate that neutralizes acid at the epithelial surface.
16
Q
What are the primary functions of the liver?
A
Bile production, detoxification, metabolism, protein synthesis, and storage of nutrients.
17
Q
What structures make up a hepatic lobule?
A
Central vein, hepatocyte plates, sinusoids, Kupffer cells, and the portal triad.
18
Q
What is the significance of the hepatic portal vein?
A
It transports nutrient-rich blood from the intestines to the liver for processing.
19
Q
How do hepatocytes contribute to metabolism?
A
They process nutrients, detoxify blood, synthesize proteins, and store glycogen.
20
Q
What is the function of the gallbladder?
A
To store and concentrate bile before releasing it into the duodenum.
21
Q
What stimulates the gallbladder to release bile?
A
Cholecystokinin (CCK), released by the small intestine when fatty food is present.
22
Q
How does the pancreas function in digestion?
A
The exocrine pancreas secretes digestive enzymes, and the endocrine pancreas regulates blood sugar.
23
Q
Which pancreatic enzymes digest proteins?
A
Trypsin, chymotrypsin, and carboxypeptidase.
24
Q
Which pancreatic enzymes digest carbohydrates and lipids?
A
Amylase (carbohydrates) and lipase (lipids).
25
What is the function of bicarbonate secreted by the pancreas?
To neutralize acidic chyme entering the small intestine.
26
What is the role of the small intestine in digestion?
Completes digestion and absorbs nutrients into the bloodstream.
27
What structures increase the surface area of the small intestine?
Plicae circulares, villi, and microvilli.
28
Which enzyme activates pancreatic zymogens?
Enteropeptidase, which converts trypsinogen into trypsin.
29
What is the function of Peyer’s patches in the ileum?
They are lymphoid nodules that protect against pathogens in the gut.
30
What is the main function of the large intestine?
Absorbs water and electrolytes, compacts feces, and houses gut microbiota.
31
What are haustra?
Sacculations of the colon formed by contractions of the teniae coli.
32
How does the appendix contribute to the immune system?
Contains lymphoid tissue that may help regulate gut bacteria.
33
What are the two types of muscle movement in the intestines?
Peristalsis (propulsion) and segmentation (mixing).
34
What are the three phases of gastric secretion?
Cephalic phase (brain response), gastric phase (stomach response), and intestinal phase (duodenal response).
35
How is glucose absorbed in the intestines?
Via sodium-glucose cotransporters (SGLT) on enterocytes.
36
Which structures form the portal triad in the liver?
A branch of the hepatic artery, portal vein, and bile duct.
37
What are the functions of Kupffer cells?
Phagocytosis of pathogens, debris, and aged red blood cells in liver sinusoids.
38
What is the role of bile salts in fat digestion?
They emulsify fats, making them accessible to lipases.
39
What is the difference between exocrine and endocrine pancreatic function?
Exocrine secretes digestive enzymes, endocrine regulates blood sugar (insulin and glucagon).
40
What causes jaundice?
Accumulation of bilirubin due to liver dysfunction or bile duct obstruction.
41
What are the main products of carbohydrate digestion?
Monosaccharides: glucose, fructose, and galactose.
42
What causes gastroesophageal reflux disease (GERD)?
Weakening of the lower esophageal sphincter, allowing acid reflux.
43
How does the gut microbiota contribute to digestion?
Produces short-chain fatty acids, synthesizes vitamins, and aids in immune regulation.
44
What is the function of the anal sphincters?
Internal sphincter (involuntary) and external sphincter (voluntary) control defecation.
45
What is the function of somatostatin in digestion?
Inhibits gastric secretion, bile release, and pancreatic enzyme secretion.
46
Which vitamins are absorbed in the large intestine?
Vitamin K and some B vitamins, produced by gut bacteria.
47
What is the function of chylomicrons?
Transport dietary lipids from the intestines to the lymphatic system.
48
What is the significance of the intrinsic factor secreted by the stomach?
Essential for vitamin B12 absorption in the ileum.
49
What is lactose intolerance?
Deficiency in lactase enzyme, leading to undigested lactose causing gastrointestinal symptoms.
50
What is celiac disease?
An autoimmune reaction to gluten that damages the small intestine's villi, reducing nutrient absorption.
51
What is the function of secretin?
Stimulates bicarbonate secretion from the pancreas to neutralize stomach acid.
52
Describe the detailed mechanism by which parietal cells secrete hydrochloric acid.
HCl secretion involves carbonic anhydrase converting CO2 and H2O into H2CO3, which dissociates into H+ and HCO3-. The H+/K+ ATPase pump actively transports H+ into the lumen in exchange for K+, while Cl- follows passively, forming HCl.
53
Explain the role of the enteric nervous system (ENS) in coordinating peristalsis.
The ENS regulates peristalsis through sensory neurons detecting stretch, interneurons processing signals, and motor neurons stimulating excitatory contraction (ACh) proximal to the bolus and inhibitory relaxation (NO) distal to the bolus.
54
What is the role of interstitial cells of Cajal in gastrointestinal motility?
They act as pacemakers in the GI tract, generating slow-wave potentials that coordinate smooth muscle contractions for peristalsis and segmentation.
55
Why does the liver receive both oxygenated and deoxygenated blood?
The hepatic artery supplies oxygen-rich blood, while the portal vein supplies nutrient-rich, deoxygenated blood for metabolic processing and detoxification.
56
Describe the enterohepatic circulation of bile salts.
Bile salts are secreted into bile, emulsify fats in the duodenum, are reabsorbed in the ileum via active transport, and return to the liver via the portal vein for reuse.
57
What molecular mechanism allows the stomach to withstand a pH of 1-2?
Tight junctions between epithelial cells prevent acid penetration, mucus with bicarbonate creates a protective pH gradient, and rapid epithelial turnover (every 3-5 days) replaces damaged cells.
58
How does pancreatic secretion adapt to varying dietary compositions?
CCK stimulates enzyme-rich secretion in response to fats and proteins, secretin triggers bicarbonate secretion in response to acid, and neural reflexes fine-tune secretion.
59
Why are zymogens secreted in an inactive form, and how are they activated?
Prevents autodigestion of the pancreas; trypsinogen is activated by enteropeptidase in the duodenum, which then activates other proteases.
60
How does the gut microbiota influence host metabolism?
Gut bacteria ferment fiber into short-chain fatty acids, regulate bile acid metabolism, influence insulin sensitivity, and modulate immune responses.
61
What is the molecular mechanism behind lactose intolerance?
Lactase deficiency prevents lactose hydrolysis into glucose and galactose, leading to osmotic diarrhea and bacterial fermentation causing gas and bloating.
62
How does vitamin B12 absorption depend on gastric and intestinal function?
Parietal cells secrete intrinsic factor, which binds B12; the complex is absorbed in the ileum via receptor-mediated endocytosis.
63
What is the role of the SGLT1 transporter in intestinal glucose absorption?
SGLT1 uses sodium gradients (Na+/K+ ATPase) to actively transport glucose into enterocytes, followed by GLUT2-mediated diffusion into the blood.
64
Describe the structural and functional differences between villi and microvilli.
Villi are macroscopic projections with blood/lymphatic vessels, while microvilli are microscopic actin-based structures forming the brush border, containing digestive enzymes.
65
What is the role of FXR (farnesoid X receptor) in bile acid homeostasis?
FXR activation in hepatocytes inhibits bile acid synthesis and enhances their enterohepatic recirculation to prevent bile acid toxicity.
66
How does ethanol metabolism contribute to fatty liver disease?
Ethanol is metabolized by alcohol dehydrogenase and CYP2E1, producing NADH, which inhibits β-oxidation and promotes fatty acid accumulation.
67
Explain the histological changes seen in Barrett’s esophagus.
Chronic acid reflux induces metaplasia, replacing nonkeratinized stratified squamous epithelium with columnar epithelium with goblet cells.
68
Why does gastric bypass surgery reduce appetite beyond mechanical restriction?
It alters gut hormone secretion (increased GLP-1, PYY), reducing hunger and enhancing insulin sensitivity.
69
What role do bile acids play in cholesterol homeostasis?
They are synthesized from cholesterol, regulate FXR, inhibit HMG-CoA reductase, and promote cholesterol excretion in bile.
70
Why is the jejunum the primary site of nutrient absorption?
It has the highest density of plicae circulares, villi, and transporters for monosaccharides, amino acids, and lipids.
71
How do Peyer’s patches influence immune tolerance in the gut?
They sample antigens, promote regulatory T-cell differentiation, and induce IgA production for mucosal immunity.
72
What triggers the migrating motor complex (MMC) in fasting conditions?
Motilin secretion stimulates periodic contractions to clear debris and bacteria from the small intestine.
73
How does the gut-brain axis regulate digestion?
Neural (vagus nerve) and hormonal signals (ghrelin, CCK) coordinate appetite, motility, and enzyme secretion.
74
Describe the mechanisms of bile acid malabsorption.
Diseases like Crohn’s reduce ileal reabsorption, leading to diarrhea and increased bile acid synthesis by the liver.
75
What causes pernicious anemia?
Autoimmune destruction of parietal cells reduces intrinsic factor secretion, leading to vitamin B12 deficiency and megaloblastic anemia.
76
How do enterochromaffin-like (ECL) cells contribute to acid secretion?
They release histamine, which activates H2 receptors on parietal cells, increasing cAMP and HCl production.
77
What is the role of Paneth cells in gut immunity?
They secrete antimicrobial peptides like defensins and lysozyme to regulate gut microbiota.
78
How do secretin and cholecystokinin (CCK) work together in digestion?
Secretin triggers bicarbonate secretion, while CCK stimulates pancreatic enzyme release and gallbladder contraction.
79
What factors regulate iron absorption in the duodenum?
Hepcidin regulates ferroportin, reducing iron export when levels are high; vitamin C enhances iron uptake by reducing Fe3+ to Fe2+.
80
81
What are the main functions of the digestive system?
Ingestion, digestion, motility, secretion, absorption, hormone release, elimination, immune defense.
82
Which layers make up the general structure of the gastrointestinal tract?
Mucosa, submucosa, muscularis externa, serosa/adventitia.
83
What are the primary functions of the small intestine?
Digestion via enzymes, absorption of ~90% of nutrients, water, and electrolytes.
84
What is the role of the myenteric (Auerbach’s) plexus in digestion?
Regulates peristalsis and the rhythmic contraction of the muscularis externa.
85
How does the stomach protect itself from acid-induced damage?
Mucus secretion with bicarbonate ions, tight junctions between cells, rapid cell turnover.
86
What are the differences between the four types of lingual papillae?
Filiform (mechanical, no taste buds), Fungiform (mushroom-shaped, taste buds), Foliate (ridges on lateral tongue, taste buds), Circumvallate (largest, taste buds on sides, von Ebner's glands).
87
How do parietal cells contribute to digestion?
Secrete hydrochloric acid (HCl) and intrinsic factor, essential for vitamin B12 absorption.
88
What is the function of the crypts of Lieberkühn in the small intestine?
Secrete enzymes, house stem cells for epithelial renewal, produce antimicrobial substances.
89
Which glands produce digestive enzymes in the pancreas?
Exocrine pancreas: acinar cells secrete amylase, lipase, proteases (trypsinogen, chymotrypsinogen).
90
How does bile aid in fat digestion?
Emulsifies fats into micelles, allowing pancreatic lipase to break them into monoglycerides and fatty acids.
91
What structures increase the absorptive surface area in the small intestine?
Plicae circulares, villi, microvilli.
92
How is glucose absorbed in the small intestine?
Via sodium-glucose co-transporters (SGLT) on enterocytes, then facilitated diffusion into capillaries.
93
What is the function of the hepatic portal vein?
Carries nutrient-rich, oxygen-depleted blood from the digestive tract to the liver for processing.
94
What are the structural components of a hepatic lobule?
Hexagonal plates of hepatocytes, central vein, portal triads, sinusoids, space of Disse.
95
How does the gallbladder concentrate bile?
By removing water and electrolytes through active transport by its epithelial cells.
96
What are Kupffer cells and their function?
Specialized macrophages in liver sinusoids, phagocytose old erythrocytes and pathogens.
97
How do chief cells contribute to digestion?
Secrete pepsinogen, which is activated into pepsin by HCl to digest proteins.
98
What is the role of enteroendocrine cells in digestion?
Secrete hormones like gastrin (stimulates acid secretion), secretin (stimulates bicarbonate), and cholecystokinin (stimulates bile release).
99
How is peristalsis regulated?
By the enteric nervous system, particularly the myenteric plexus, under autonomic nervous system influence.
100
What is Barrett’s esophagus and its significance?
Metaplastic transformation of esophageal epithelium due to acid reflux, increasing cancer risk.
101
What is the function of parietal cells?
Secrete hydrochloric acid and intrinsic factor.
102
What type of epithelium lines the gallbladder?
Simple columnar epithelium.
103
What is the function of the muscularis externa's longitudinal layer?
Shortens the digestive tract to propel content.
104
Where are Ito cells located and what do they store?
In the space of Disse; store vitamin A.
105
What cell type secretes lysozyme and defensins in the small intestine?
Paneth cells.
106
What condition results from chronic acid reflux damaging the esophagus?
Barrett’s esophagus.
107
Which cells secrete pepsinogen?
Chief cells.
108
What is the function of the vermilion zone of the lips?
Provides sensory innervation and lacks salivary/sweat glands.
109
What are the permanent folds in the small intestine called?
Plicae circularis or valves of Kerckring.
110
Which organ is primarily responsible for absorption of nutrients?
Small intestine.
111
What cells line the hepatic sinusoids?
Endothelial and Kupffer cells.
112
What are centroacinar cells?
Cells within pancreatic acini that mark the start of the intercalated duct.
113
What are the teniae coli?
Three longitudinal bands of smooth muscle in the colon.
114
Which phase of gastric secretion is triggered by stomach distension and peptides?
The gastric phase.
115
What feature is absent in the gallbladder mucosa?
Muscularis mucosae.
116
How often are surface mucous cells renewed?
Every 3-5 days.
117
What kind of epithelium lines the stomach?
Simple columnar epithelium.
118
What is the main immune structure found throughout the GI tract?
GALT (Gut-Associated Lymphoid Tissue).
119
Which tongue papillae contain von Ebner’s glands?
Circumvallate papillae.
120
Which hormone stimulates pancreatic bicarbonate secretion?
Secretin.
121
What is the turnover time for neuroepithelial cells in taste buds?
Approximately 10 days.
122
Which condition is associated with obstruction of the appendix?
Appendicitis.
123
What is the effect of glucagon on blood glucose?
Increases blood glucose levels.
124
Where is lining mucosa located?
In the lips, cheeks, floor of the mouth, inferior surfaces of the tongue, and soft palate.
125
Which papillae are responsible for mechanical manipulation but lack taste buds?
Filiform papillae.
126
What is the function of the large intestine?
Reabsorption of water and electrolytes; formation of feces.
127
What glands are found in the esophageal submucosa?
Compound tubuloalveolar esophageal glands.
128
What type of epithelium is found in masticatory mucosa?
Keratinized or parakeratinized stratified squamous epithelium.
129
Where are cardiac glands located in the stomach?
In the cardia region near the gastroesophageal junction.
130
Which enzyme activates pancreatic zymogens?
Enteropeptidase.
131
How are long-chain fatty acids absorbed in enterocytes?
They are resynthesized into triglycerides and transported as chylomicrons.
132
Which nerve plexus regulates peristalsis?
Auerbach’s (myenteric) plexus.
133
Where are foliate papillae located?
On the lateral edge of the tongue.
134
Which cranial nerves are involved in taste sensation?
Facial (VII), Glossopharyngeal (IX), and Vagus (X).
135
What is the role of the submucosa?
Supports the mucosa and contains blood vessels, glands, and Meissner’s plexus.
136
What is the role of enteroendocrine G cells in the stomach?
They secrete gastrin.
137
What structures form the portal triad?
Branch of bile duct, hepatic artery, and portal vein.
138
What is the function of bile canaliculi?
Collect bile secreted by hepatocytes.
139
What is the structural unit of the liver?
Hepatic lobule.
140
Which pancreatic cells secrete insulin?
Beta cells in the islets of Langerhans.
141
What is the role of the gallbladder?
Stores and concentrates bile.
142
What kind of muscle is found in the upper third of the esophageal muscularis externa?
Striated muscle.
143
What initiates the cephalic phase of gastric secretion?
Sight, smell, thought, or taste of food.
144
Which cells in the pancreas secrete somatostatin?
Delta (D) cells.
145
What is the function of M cells in the small intestine?
Transport antigens to immune cells in Peyer’s patches.
146
What are the three layers of lining mucosa epithelium?
Stratum basale, stratum spinosum, and stratum superficiale.
147
What type of glands are found in the lips' internal mucous surface?
Minor salivary glands.
148
What is the primary role of the lingual tonsils?
Provide immune defense as part of MALT.
149
What are the three main cell types in taste buds?
Neuroepithelial (sensory), supporting, and basal cells.
150
What is the role of the taste pore?
Allows tastants to reach taste receptor cells.
151
Which ion is responsible for salty taste?
Na+ or K+ ions.
152
Which molecules stimulate umami taste?
Amino acids like glutamate and aspartate.
153
Where are esophageal cardiac glands located?
In the lamina propria near the stomach.
154
Which plexus controls the muscularis externa of the esophagus?
Auerbach’s (myenteric) plexus.
155
What is the function of the pharyngoesophageal sphincter?
Prevents entry of air into the esophagus.
156
What distinguishes the pyloric glands from fundic glands?
Pyloric glands have wider lumens and secrete mucus and lysozyme.
157
What triggers parietal cells to secrete HCl?
Stimulation by gastrin, histamine, and nerve signals.
158
What is the function of the tubulovesicular membrane system in parietal cells?
Stores H+/K+ ATPase pumps in inactive cells.
159
How is pepsinogen activated in the stomach?
Converted to pepsin by hydrochloric acid.
160
What is the function of enterocytes?
Absorb nutrients from the intestinal lumen into blood and lymph.
161
What is the brush border composed of?
Microvilli on the apical surface of enterocytes.
162
What is the role of lacteals in the villi?
Absorb long-chain fatty acids and transport them as chylomicrons.
163
Where are Brunner’s glands located?
In the submucosa of the duodenum.
164
What is the function of secretin?
Stimulates bicarbonate secretion from the pancreas.
165
Which hormone increases gallbladder contraction?
Cholecystokinin (CCK).
166
Which hormone inhibits gastric secretion and motility?
Gastric inhibitory peptide (GIP).
167
What is the main difference between small and large intestine mucosa?
The large intestine lacks villi and has more goblet cells.
168
What are haustra?
Sacculations of the colon formed by the teniae coli.
169
What causes the formation of teniae coli?
Thickening of the outer longitudinal muscle layer.
170
Which vein supplies nutrient-rich blood to the liver?
Portal vein.
171
What is the function of Kupffer cells?
Phagocytose old erythrocytes and present antigens.
172
What happens in the space of Disse?
Exchange of substances between blood and hepatocytes.
173
How does the gallbladder concentrate bile?
By removing water and electrolytes.
174
What condition is associated with cholesterol saturation in bile?
Gallstone formation.
175
Which enzymes are secreted in inactive form by the pancreas?
Trypsinogen, chymotrypsinogen, and pro-carboxypeptidase.
176
What is the role of intercalated ducts in the pancreas?
Add bicarbonate to neutralize acidic chyme.
177
What triggers acinar cell secretion in the pancreas?
CCK and parasympathetic stimulation.
178
Which pancreatic cell type is most numerous in islets?
Beta cells.
179
What is the main role of insulin?
Promotes glucose uptake and glycogen synthesis.
180
What is the function of somatostatin?
Inhibits insulin and glucagon secretion.
181
What type of connective tissue is found in the submucosa?
Dense irregular connective tissue.
182
What is the function of the muscularis mucosae?
Enables localized movements of the mucosa.
183
Where is adventitia found instead of serosa?
In the esophagus and anal canal.
184
What is the role of Meissner’s plexus?
Controls secretion and blood flow in the submucosa.
185
What is peristalsis?
Rhythmic contraction of the muscularis externa to move contents through the GI tract.
186
What are the major salivary glands?
Parotid, submandibular, and sublingual.
187
What is the primary secretion type of the parotid gland?
Serous.
188
Which salivary gland produces the most saliva?
Submandibular gland.
189
What are serous demilunes?
Crescent-shaped serous cells capping mucous tubules.
190
What is the function of striated ducts in salivary glands?
Reabsorb sodium and secrete potassium and bicarbonate.
191
Which enzyme in saliva begins starch digestion?
Amylase.
192
What immunoglobulin is secreted in saliva?
IgA.
193
What is the function of myoepithelial cells?
Contract to help expel secretions from glandular acini.
194
What ducts modify saliva by ion transport? (Detailed) (Detailed) (Detailed) (Detailed)
Striated ducts.
195
What is the function of the gallbladder? (Detailed)
Stores and concentrates bile.
196
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
197
What do acinar cells secrete? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
198
What epithelial type lines the gallbladder?
Simple columnar with short microvilli.
199
Which hormone is secreted by G cells?
Gastrin.
200
What do acinar cells secrete? (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
201
What do Ito cells store and produce? (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
202
What hormones do alpha and beta cells secrete?
Alpha: glucagon; Beta: insulin.
203
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed)
Every 3–5 days.
204
What do Paneth cells secrete? (Detailed) (Detailed)
Lysozyme and defensins.
205
Which salivary gland is purely serous? (Detailed) (Detailed)
Parotid gland.
206
What is the function of Kupffer cells? (Detailed) (Detailed)
Phagocytosis and antigen presentation.
207
What are the components of the portal triad? (Detailed) (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
208
What is the function of Kupffer cells?
Phagocytosis and antigen presentation.
209
What do acinar cells secrete? (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
210
What are the three structural adaptations for absorption? (Detailed) (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
211
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
212
What is the function of Kupffer cells? (Detailed)
Phagocytosis and antigen presentation.
213
What is prominent in the appendix mucosa? (Detailed)
Lymphoid nodules (GALT).
214
What are the components of the portal triad? (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
215
What are the three regions of the stomach? (Detailed)
Cardia, fundus/body, pylorus.
216
What cells make up taste buds? (Detailed)
Neuroepithelial (sensory), supporting, and basal cells.
217
What are the two main gland types in the esophagus? (Detailed) (Detailed)
Cardiac glands and esophageal glands proper.
218
What is secreted by chief cells?
Pepsinogen and gastric lipase.
219
What ducts modify saliva by ion transport? (Detailed) (Detailed) (Detailed)
Striated ducts.
220
What are the three structural adaptations for absorption? (Detailed)
Plicae circularis, villi, and microvilli.
221
What is the epithelial transition in the anal canal? (Detailed)
Simple columnar to stratified squamous.
222
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
223
What are teniae coli?
Three longitudinal muscle bands of the colon.
224
Which papillae of the tongue lack taste buds?
Filiform papillae.
225
What is the epithelial transition in the anal canal?
Simple columnar to stratified squamous.
226
What immune component is secreted in saliva? (Detailed) (Detailed) (Detailed) (Detailed)
IgA.
227
What do Ito cells store and produce?
Vitamin A and collagen (in fibrosis).
228
What are the components of the portal triad?
Portal vein, hepatic artery, bile duct.
229
What is the role of centroacinar cells? (Detailed) (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
230
What condition results from chronic acid reflux? (Detailed)
Barrett's esophagus.
231
What ducts modify saliva by ion transport? (Detailed)
Striated ducts.
232
Which salivary gland is purely serous?
Parotid gland.
233
Which cranial nerves innervate taste buds?
VII, IX, and X.
234
What muscle types are found along the esophagus? (Detailed) (Detailed) (Detailed)
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
235
What is secreted by chief cells? (Detailed)
Pepsinogen and gastric lipase.
236
What immune component is secreted in saliva? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
IgA.
237
What distinguishes the large intestine mucosa?
No villi, many crypts, abundant goblet cells.
238
Which hormone is secreted by G cells? (Detailed)
Gastrin.
239
What are the three structural adaptations for absorption? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
240
What are the components of the portal triad? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
241
What is secreted by parietal cells? (Detailed)
HCl and intrinsic factor.
242
What are the functions of CCK and secretin? (Detailed) (Detailed) (Detailed)
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
243
What type of epithelium lines the esophagus?
Nonkeratinized stratified squamous.
244
What is the role of centroacinar cells? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
245
What are teniae coli? (Detailed)
Three longitudinal muscle bands of the colon.
246
What is the function of the gallbladder?
Stores and concentrates bile.
247
What type of epithelium lines the esophagus? (Detailed) (Detailed) (Detailed)
Nonkeratinized stratified squamous.
248
What are the components of the portal triad? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
249
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Parotid gland.
250
What ducts modify saliva by ion transport?
Striated ducts.
251
What are the functions of CCK and secretin?
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
252
What is the role of centroacinar cells? (Detailed) (Detailed) (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
253
What do Paneth cells secrete? (Detailed)
Lysozyme and defensins.
254
Which salivary gland is purely serous? (Detailed)
Parotid gland.
255
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed)
Parotid gland.
256
What is secreted by chief cells? (Detailed) (Detailed)
Pepsinogen and gastric lipase.
257
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
258
What is the function of the gallbladder? (Detailed) (Detailed)
Stores and concentrates bile.
259
What is prominent in the appendix mucosa? (Detailed) (Detailed)
Lymphoid nodules (GALT).
260
What is the role of centroacinar cells? (Detailed)
Start the intercalated duct and secrete bicarbonate.
261
What are the three regions of the stomach? (Detailed) (Detailed)
Cardia, fundus/body, pylorus.
262
Which hormone is secreted by G cells? (Detailed) (Detailed) (Detailed) (Detailed)
Gastrin.
263
What do acinar cells secrete? (Detailed) (Detailed) (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
264
What do Paneth cells secrete?
Lysozyme and defensins.
265
What immune component is secreted in saliva? (Detailed) (Detailed) (Detailed)
IgA.
266
What distinguishes the large intestine mucosa? (Detailed) (Detailed) (Detailed) (Detailed)
No villi, many crypts, abundant goblet cells.
267
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Every 3–5 days.
268
What are the components of the portal triad? (Detailed)
Portal vein, hepatic artery, bile duct.
269
What are the three structural adaptations for absorption? (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
270
What is the role of Auerbach's plexus?
Coordinates peristalsis via muscularis externa.
271
What type of epithelium lines the esophagus? (Detailed) (Detailed)
Nonkeratinized stratified squamous.
272
Which papillae of the tongue lack taste buds? (Detailed)
Filiform papillae.
273
What are teniae coli? (Detailed) (Detailed)
Three longitudinal muscle bands of the colon.
274
What is prominent in the appendix mucosa? (Detailed) (Detailed) (Detailed)
Lymphoid nodules (GALT).
275
Which hormone is secreted by G cells? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Gastrin.
276
What is secreted by parietal cells?
HCl and intrinsic factor.
277
What condition results from chronic acid reflux?
Barrett's esophagus.
278
What distinguishes the large intestine mucosa? (Detailed) (Detailed) (Detailed)
No villi, many crypts, abundant goblet cells.
279
What cells make up taste buds? (Detailed) (Detailed)
Neuroepithelial (sensory), supporting, and basal cells.
280
What cells make up taste buds? (Detailed) (Detailed) (Detailed)
Neuroepithelial (sensory), supporting, and basal cells.
281
Which hormone is secreted by G cells? (Detailed) (Detailed) (Detailed)
Gastrin.
282
What type of epithelium lines the esophagus? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Nonkeratinized stratified squamous.
283
Which hormone is secreted by G cells? (Detailed) (Detailed)
Gastrin.
284
What is the role of centroacinar cells?
Start the intercalated duct and secrete bicarbonate.
285
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
286
How often are surface mucous cells renewed?
Every 3–5 days.
287
What hormones do alpha and beta cells secrete? (Detailed)
Alpha: glucagon; Beta: insulin.
288
What are the three structural adaptations for absorption?
Plicae circularis, villi, and microvilli.
289
What muscle types are found along the esophagus? (Detailed)
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
290
What are the three regions of the stomach? (Detailed) (Detailed) (Detailed) (Detailed)
Cardia, fundus/body, pylorus.
291
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed) (Detailed)
Parotid gland.
292
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Parotid gland.
293
What immune component is secreted in saliva? (Detailed)
IgA.
294
What immune component is secreted in saliva?
IgA.
295
Where are Brunner’s glands found?
In the submucosa of the duodenum.
296
What is the role of centroacinar cells? (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
297
What are the three types of oral mucosa?
Masticatory, lining, and specialized.
298
Where are Brunner’s glands found? (Detailed) (Detailed)
In the submucosa of the duodenum.
299
What do Paneth cells secrete? (Detailed) (Detailed) (Detailed) (Detailed)
Lysozyme and defensins.
300
What distinguishes the large intestine mucosa? (Detailed) (Detailed)
No villi, many crypts, abundant goblet cells.
301
What are the two main gland types in the esophagus? (Detailed)
Cardiac glands and esophageal glands proper.
302
What is the role of Auerbach's plexus? (Detailed)
Coordinates peristalsis via muscularis externa.
303
Which cranial nerves innervate taste buds? (Detailed)
VII, IX, and X.
304
What immune component is secreted in saliva? (Detailed) (Detailed)
IgA.
305
What are the four histological layers of the digestive tract?
Mucosa, submucosa, muscularis externa, serosa/adventitia.
306
What are the three regions of the stomach?
Cardia, fundus/body, pylorus.
307
What cells make up taste buds?
Neuroepithelial (sensory), supporting, and basal cells.
308
What distinguishes the large intestine mucosa? (Detailed)
No villi, many crypts, abundant goblet cells.
309
What are the three regions of the stomach? (Detailed) (Detailed) (Detailed)
Cardia, fundus/body, pylorus.
310
What are the three types of oral mucosa? (Detailed)
Masticatory, lining, and specialized.
311
What ducts modify saliva by ion transport? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Striated ducts.
312
What plexus is found in the submucosa and what is its role?
Meissner’s plexus; regulates secretion and blood flow.
313
What are the two main gland types in the esophagus?
Cardiac glands and esophageal glands proper.
314
What are the functions of CCK and secretin? (Detailed) (Detailed)
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
315
What condition results from chronic acid reflux? (Detailed) (Detailed)
Barrett's esophagus.
316
What do Paneth cells secrete? (Detailed) (Detailed) (Detailed)
Lysozyme and defensins.
317
What are the functions of CCK and secretin? (Detailed)
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
318
What ducts modify saliva by ion transport? (Detailed) (Detailed)
Striated ducts.
319
What type of epithelium lines the esophagus? (Detailed) (Detailed) (Detailed) (Detailed)
Nonkeratinized stratified squamous.
320
What plexus is found in the submucosa and what is its role? (Detailed)
Meissner’s plexus; regulates secretion and blood flow.
321
What type of epithelium lines the esophagus? (Detailed)
Nonkeratinized stratified squamous.
322
What do acinar cells secrete? (Detailed) (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
323
What are the components of the portal triad? (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
324
Which papillae of the tongue lack taste buds? (Detailed) (Detailed)
Filiform papillae.
325
How often are surface mucous cells renewed? (Detailed)
Every 3–5 days.
326
What are the three structural adaptations for absorption? (Detailed) (Detailed) (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
327
What hormones do alpha and beta cells secrete? (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
328
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed) (Detailed)
Every 3–5 days.
329
What are the four histological layers of the digestive tract? (Detailed)
Mucosa, submucosa, muscularis externa, serosa/adventitia.
330
What is secreted by chief cells? (Detailed) (Detailed) (Detailed)
Pepsinogen and gastric lipase.
331
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
332
What plexus is found in the submucosa and what is its role? (Detailed) (Detailed)
Meissner’s plexus; regulates secretion and blood flow.
333
What do acinar cells secrete?
Digestive enzymes (e.g., amylase, lipase, proteases).
334
How often are surface mucous cells renewed? (Detailed) (Detailed)
Every 3–5 days.
335
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
336
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Every 3–5 days.
337
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
338
What is prominent in the appendix mucosa?
Lymphoid nodules (GALT).
339
What muscle types are found along the esophagus?
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
340
What epithelial type lines the gallbladder? (Detailed)
Simple columnar with short microvilli.
341
What muscle types are found along the esophagus? (Detailed) (Detailed)
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
342
What do Ito cells store and produce? (Detailed)
Vitamin A and collagen (in fibrosis).
343
Where are Brunner’s glands found? (Detailed)
In the submucosa of the duodenum.
344
What ducts modify saliva by ion transport? (Detailed) (Detailed) (Detailed) (Detailed)
Striated ducts.
345
What is the function of the gallbladder? (Detailed)
Stores and concentrates bile.
346
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
347
What do acinar cells secrete? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
348
What epithelial type lines the gallbladder?
Simple columnar with short microvilli.
349
Which hormone is secreted by G cells?
Gastrin.
350
What do acinar cells secrete? (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
351
What do Ito cells store and produce? (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
352
What hormones do alpha and beta cells secrete?
Alpha: glucagon; Beta: insulin.
353
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed)
Every 3–5 days.
354
What do Paneth cells secrete? (Detailed) (Detailed)
Lysozyme and defensins.
355
Which salivary gland is purely serous? (Detailed) (Detailed)
Parotid gland.
356
What is the function of Kupffer cells? (Detailed) (Detailed)
Phagocytosis and antigen presentation.
357
What are the components of the portal triad? (Detailed) (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
358
What is the function of Kupffer cells?
Phagocytosis and antigen presentation.
359
What do acinar cells secrete? (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
360
What are the three structural adaptations for absorption? (Detailed) (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
361
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
362
What is the function of Kupffer cells? (Detailed)
Phagocytosis and antigen presentation.
363
What is prominent in the appendix mucosa? (Detailed)
Lymphoid nodules (GALT).
364
What are the components of the portal triad? (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
365
What are the three regions of the stomach? (Detailed)
Cardia, fundus/body, pylorus.
366
What cells make up taste buds? (Detailed)
Neuroepithelial (sensory), supporting, and basal cells.
367
What are the two main gland types in the esophagus? (Detailed) (Detailed)
Cardiac glands and esophageal glands proper.
368
What is secreted by chief cells?
Pepsinogen and gastric lipase.
369
What ducts modify saliva by ion transport? (Detailed) (Detailed) (Detailed)
Striated ducts.
370
What are the three structural adaptations for absorption? (Detailed)
Plicae circularis, villi, and microvilli.
371
What is the epithelial transition in the anal canal? (Detailed)
Simple columnar to stratified squamous.
372
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
373
What are teniae coli?
Three longitudinal muscle bands of the colon.
374
Which papillae of the tongue lack taste buds?
Filiform papillae.
375
What is the epithelial transition in the anal canal?
Simple columnar to stratified squamous.
376
What immune component is secreted in saliva? (Detailed) (Detailed) (Detailed) (Detailed)
IgA.
377
What do Ito cells store and produce?
Vitamin A and collagen (in fibrosis).
378
What are the components of the portal triad?
Portal vein, hepatic artery, bile duct.
379
What is the role of centroacinar cells? (Detailed) (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
380
What condition results from chronic acid reflux? (Detailed)
Barrett's esophagus.
381
What ducts modify saliva by ion transport? (Detailed)
Striated ducts.
382
Which salivary gland is purely serous?
Parotid gland.
383
Which cranial nerves innervate taste buds?
VII, IX, and X.
384
What muscle types are found along the esophagus? (Detailed) (Detailed) (Detailed)
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
385
What is secreted by chief cells? (Detailed)
Pepsinogen and gastric lipase.
386
What immune component is secreted in saliva? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
IgA.
387
What distinguishes the large intestine mucosa?
No villi, many crypts, abundant goblet cells.
388
Which hormone is secreted by G cells? (Detailed)
Gastrin.
389
What are the three structural adaptations for absorption? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
390
What are the components of the portal triad? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
391
What is secreted by parietal cells? (Detailed)
HCl and intrinsic factor.
392
What are the functions of CCK and secretin? (Detailed) (Detailed) (Detailed)
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
393
What type of epithelium lines the esophagus?
Nonkeratinized stratified squamous.
394
What is the role of centroacinar cells? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
395
What are teniae coli? (Detailed)
Three longitudinal muscle bands of the colon.
396
What is the function of the gallbladder?
Stores and concentrates bile.
397
What type of epithelium lines the esophagus? (Detailed) (Detailed) (Detailed)
Nonkeratinized stratified squamous.
398
What are the components of the portal triad? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
399
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Parotid gland.
400
What ducts modify saliva by ion transport?
Striated ducts.
401
What are the functions of CCK and secretin?
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
402
What is the role of centroacinar cells? (Detailed) (Detailed) (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
403
What do Paneth cells secrete? (Detailed)
Lysozyme and defensins.
404
Which salivary gland is purely serous? (Detailed)
Parotid gland.
405
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed)
Parotid gland.
406
What is secreted by chief cells? (Detailed) (Detailed)
Pepsinogen and gastric lipase.
407
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
408
What is the function of the gallbladder? (Detailed) (Detailed)
Stores and concentrates bile.
409
What is prominent in the appendix mucosa? (Detailed) (Detailed)
Lymphoid nodules (GALT).
410
What is the role of centroacinar cells? (Detailed)
Start the intercalated duct and secrete bicarbonate.
411
What are the three regions of the stomach? (Detailed) (Detailed)
Cardia, fundus/body, pylorus.
412
Which hormone is secreted by G cells? (Detailed) (Detailed) (Detailed) (Detailed)
Gastrin.
413
What do acinar cells secrete? (Detailed) (Detailed) (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
414
What do Paneth cells secrete?
Lysozyme and defensins.
415
What immune component is secreted in saliva? (Detailed) (Detailed) (Detailed)
IgA.
416
What distinguishes the large intestine mucosa? (Detailed) (Detailed) (Detailed) (Detailed)
No villi, many crypts, abundant goblet cells.
417
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Every 3–5 days.
418
What are the components of the portal triad? (Detailed)
Portal vein, hepatic artery, bile duct.
419
What are the three structural adaptations for absorption? (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
420
What is the role of Auerbach's plexus?
Coordinates peristalsis via muscularis externa.
421
What type of epithelium lines the esophagus? (Detailed) (Detailed)
Nonkeratinized stratified squamous.
422
Which papillae of the tongue lack taste buds? (Detailed)
Filiform papillae.
423
What are teniae coli? (Detailed) (Detailed)
Three longitudinal muscle bands of the colon.
424
What is prominent in the appendix mucosa? (Detailed) (Detailed) (Detailed)
Lymphoid nodules (GALT).
425
Which hormone is secreted by G cells? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Gastrin.
426
What is secreted by parietal cells?
HCl and intrinsic factor.
427
What condition results from chronic acid reflux?
Barrett's esophagus.
428
What distinguishes the large intestine mucosa? (Detailed) (Detailed) (Detailed)
No villi, many crypts, abundant goblet cells.
429
What cells make up taste buds? (Detailed) (Detailed)
Neuroepithelial (sensory), supporting, and basal cells.
430
What cells make up taste buds? (Detailed) (Detailed) (Detailed)
Neuroepithelial (sensory), supporting, and basal cells.
431
Which hormone is secreted by G cells? (Detailed) (Detailed) (Detailed)
Gastrin.
432
What type of epithelium lines the esophagus? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Nonkeratinized stratified squamous.
433
Which hormone is secreted by G cells? (Detailed) (Detailed)
Gastrin.
434
What is the role of centroacinar cells?
Start the intercalated duct and secrete bicarbonate.
435
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
436
How often are surface mucous cells renewed?
Every 3–5 days.
437
What hormones do alpha and beta cells secrete? (Detailed)
Alpha: glucagon; Beta: insulin.
438
What are the three structural adaptations for absorption?
Plicae circularis, villi, and microvilli.
439
What muscle types are found along the esophagus? (Detailed)
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
440
What are the three regions of the stomach? (Detailed) (Detailed) (Detailed) (Detailed)
Cardia, fundus/body, pylorus.
441
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed) (Detailed)
Parotid gland.
442
Which salivary gland is purely serous? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Parotid gland.
443
What immune component is secreted in saliva? (Detailed)
IgA.
444
What immune component is secreted in saliva?
IgA.
445
Where are Brunner’s glands found?
In the submucosa of the duodenum.
446
What is the role of centroacinar cells? (Detailed) (Detailed)
Start the intercalated duct and secrete bicarbonate.
447
What are the three types of oral mucosa?
Masticatory, lining, and specialized.
448
Where are Brunner’s glands found? (Detailed) (Detailed)
In the submucosa of the duodenum.
449
What do Paneth cells secrete? (Detailed) (Detailed) (Detailed) (Detailed)
Lysozyme and defensins.
450
What distinguishes the large intestine mucosa? (Detailed) (Detailed)
No villi, many crypts, abundant goblet cells.
451
What are the two main gland types in the esophagus? (Detailed)
Cardiac glands and esophageal glands proper.
452
What is the role of Auerbach's plexus? (Detailed)
Coordinates peristalsis via muscularis externa.
453
Which cranial nerves innervate taste buds? (Detailed)
VII, IX, and X.
454
What immune component is secreted in saliva? (Detailed) (Detailed)
IgA.
455
What are the four histological layers of the digestive tract?
Mucosa, submucosa, muscularis externa, serosa/adventitia.
456
What are the three regions of the stomach?
Cardia, fundus/body, pylorus.
457
What cells make up taste buds?
Neuroepithelial (sensory), supporting, and basal cells.
458
What distinguishes the large intestine mucosa? (Detailed)
No villi, many crypts, abundant goblet cells.
459
What are the three regions of the stomach? (Detailed) (Detailed) (Detailed)
Cardia, fundus/body, pylorus.
460
What are the three types of oral mucosa? (Detailed)
Masticatory, lining, and specialized.
461
What ducts modify saliva by ion transport? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Striated ducts.
462
What plexus is found in the submucosa and what is its role?
Meissner’s plexus; regulates secretion and blood flow.
463
What are the two main gland types in the esophagus?
Cardiac glands and esophageal glands proper.
464
What are the functions of CCK and secretin? (Detailed) (Detailed)
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
465
What condition results from chronic acid reflux? (Detailed) (Detailed)
Barrett's esophagus.
466
What do Paneth cells secrete? (Detailed) (Detailed) (Detailed)
Lysozyme and defensins.
467
What are the functions of CCK and secretin? (Detailed)
CCK stimulates bile/pancreatic enzymes; secretin stimulates bicarbonate.
468
What ducts modify saliva by ion transport? (Detailed) (Detailed)
Striated ducts.
469
What type of epithelium lines the esophagus? (Detailed) (Detailed) (Detailed) (Detailed)
Nonkeratinized stratified squamous.
470
What plexus is found in the submucosa and what is its role? (Detailed)
Meissner’s plexus; regulates secretion and blood flow.
471
What type of epithelium lines the esophagus? (Detailed)
Nonkeratinized stratified squamous.
472
What do acinar cells secrete? (Detailed) (Detailed) (Detailed)
Digestive enzymes (e.g., amylase, lipase, proteases).
473
What are the components of the portal triad? (Detailed) (Detailed) (Detailed)
Portal vein, hepatic artery, bile duct.
474
Which papillae of the tongue lack taste buds? (Detailed) (Detailed)
Filiform papillae.
475
How often are surface mucous cells renewed? (Detailed)
Every 3–5 days.
476
What are the three structural adaptations for absorption? (Detailed) (Detailed) (Detailed) (Detailed)
Plicae circularis, villi, and microvilli.
477
What hormones do alpha and beta cells secrete? (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
478
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed) (Detailed)
Every 3–5 days.
479
What are the four histological layers of the digestive tract? (Detailed)
Mucosa, submucosa, muscularis externa, serosa/adventitia.
480
What is secreted by chief cells? (Detailed) (Detailed) (Detailed)
Pepsinogen and gastric lipase.
481
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
482
What plexus is found in the submucosa and what is its role? (Detailed) (Detailed)
Meissner’s plexus; regulates secretion and blood flow.
483
What do acinar cells secrete?
Digestive enzymes (e.g., amylase, lipase, proteases).
484
How often are surface mucous cells renewed? (Detailed) (Detailed)
Every 3–5 days.
485
What do Ito cells store and produce? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Vitamin A and collagen (in fibrosis).
486
How often are surface mucous cells renewed? (Detailed) (Detailed) (Detailed) (Detailed) (Detailed)
Every 3–5 days.
487
What hormones do alpha and beta cells secrete? (Detailed) (Detailed) (Detailed) (Detailed)
Alpha: glucagon; Beta: insulin.
488
What is prominent in the appendix mucosa?
Lymphoid nodules (GALT).
489
What muscle types are found along the esophagus?
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
490
What epithelial type lines the gallbladder? (Detailed)
Simple columnar with short microvilli.
491
What muscle types are found along the esophagus? (Detailed) (Detailed)
Upper 1/3: striated, middle: mixed, lower 1/3: smooth.
492
What do Ito cells store and produce? (Detailed)
Vitamin A and collagen (in fibrosis).
493
Where are Brunner’s glands found? (Detailed)
In the submucosa of the duodenum.
