Exam 3 Alimentary canal Flashcards
1
Q
The alimentary canal is the _____ portion of the GI tract
A
Tubular
2
Q
What is the alimentary canal a continuation of?
A
oral cavity
3
Q
What happens to food in the alimentary canal?
A
- churned
- liquefied
- digested
4
Q
_____ and ____ is absorbed in the alimentary canal
A
Nutrients and water
5
Q
Indigestible components are:
A
Eliminated (feces)
6
Q
How long is the alimentary canal?
A
9 meters
7
Q
What are the morphological regions of the alimentary canal?
A
- esophagus
- stomach
- small intestine
- large intestine
8
Q
What are the portions of the stomach?
A
Cardiac, fundus, body, pylorus
9
Q
Small intestine is made up of what components?
A
- duodenum
- jejunum
- ileum
10
Q
Components of the large intestine
A
- cecum
- colon
- rectum
- anal canal
- appendix
11
Q
From inside to out,
What is the general plan of the alimentary canal?
A
- Mucosa
- Submucosa
- Muscularis Externa
- Adventitia/serosa
organized in tubular structure
12
Q
The alimentary canal has the same ____ throughout, with some ____
A
“plan”; regional differences
13
Q
What makes up the mucosa of the GI tract/alimentary canal?
A
- epithelium
- lamina propria
- muscularis mucosa (smooth muscle)
14
Q
Where are glands found in the mucosa of the GI tract?
A
Lamina propria
15
Q
What layer of the GI tract mucosa is highly vascular and contains lymph vessels and loose CT?
A
Lamina propria
16
Q
Functions of the alimentary canal mucosa
A
- barrier
- secretory
- absorptive
17
Q
The lumen of the GI is continuous with the:
A
Environment
18
Q
The muscularis mucosa is composed of:
A
- smooth muscle
- inner circular and outer longitudinal
19
Q
GI submucosa is composed of what kind of connective tissue?
A
- dense
- irregular
- fibroelastic
20
Q
Are there glands in the submucosa?
A
No (except esophagus and duodenum)
21
Q
Meissner’s submucosal plexus is found in:
A
Submucosa of the GI tract (within submucosal CT)
22
Q
Meissner’s submucosal plexus controls what?
A
- motility of mucosa
- secretory activity of glands
- blood flow
23
Q
What are the layers of smooth muscle in the muscularis externa?
A
- inner circular
- outer longitudinal
24
Q
Contraction in the muscularis externa produces:
A
Propulsion/peristalsis
25
Where is Auerbach's myenteric plexus found?
Between inner circular and outer longitudinal smooth muscle
26
Auerbach's myenteric plexus regulates:
Muscle activity
27
Inner circular smooth muscle is seen from a ____ profile
longitudinal
28
Outer longitudinal smooth muscle is seen from a ____ profile
Cross section
29
What is the function of adventitia?
Adheres/anchors organs together
30
What is the function of serosa?
Allows organs to slide past one another
31
Intraperitoneal contains:
- serosa
- simple squamous epithelium
32
Retroperitoneal contains:
- adventitia
- dense, irregular CT that adheres to body wall
33
What innervates the GI tract?
- autonomic nervous system
- enteric nervous system
34
What are the components of the autonomic nervous system?
- Sympathetic
- Parasympathetic
35
What are the components of the enteric nervous system?
- Meissner's submucosal plecus
- Auerbach's myenteric plexus
36
True or false: the enteric nervous system can control the GI tract independent of the ANS
True
37
Where is Auerbach's Myenteric Plexus located?
Between smooth muscle layers of muscularis externa
38
Auerbach's Myenteric Plexus contains:
Nerve fibers and cell bodies
39
Auerbach's Myenteric Plexus is ____ plexus that extends from the ____ to the ____
One; esophagus to anus
| monitors entire GI tract
40
Large neuronal cell bodies and satellite cells are found in:
Auerbach's Myenteric Plexus
41
_____ is important for local control of the GI tract
Meissner's Submucosal Plexus
42
The esophagus is a _____ tube
Muscular
43
How long is the esophagus?
25 cm
44
Functions of the esophagus
- receives food from the pharynx
- discharges food to the stomach
- prevents retrograde flow of gastric acid
45
The tunica in the esophagus is clearly evident, containint:
- mucosa
- submucosa
- tunica muscularis externa
- lumen
46
True or false: the esophagus closes during swallowing
False - opens to receive bolus
47
The esophagus is _____ - contains puckered folds, collapsed
Distensible
48
The esophageal mucosa has 3 layers, which are:
- epithelium
- lamina propria
- muscularis mucosa
49
Esophageal mucosa epithelium contains:
nonkeratinized stratified squamous
50
Esophageal mucosa lamina propria contains:
- fibroelastic
- esophageal cardiac glands
51
Where are esophageal cardiac glands located?
Near pharynx, stomach
52
Esophageal cardiac glands produce:
Mucus
53
Esophageal mucosa - describe the muscularis mucosa
- Only a single layer of longitudinally arranged smooth muscle
- becomes thicker near stomach
54
Esophageal mucosa is classified as either:
- unremarkable
- remarkable
55
Describe unremarkable esophageal submucosa
- dense, fibroelastic CT
- contains Meissner's Submucosal Plexus
56
Remarkable esophageal submucosa contains:
contains esophageal glands proper
| one of only two regions with glands in submucosa
57
Esophageal glands proper are located outside of:
Muscularis mucosa
58
Esophageal glands are what type of glands?
Tubuloacinar glands
59
Tubuloacinar glands contain what kind of cells?
- mucous cells
- serous cells
60
Esophageal glands proper deliver secretions into the:
Lumen
61
Esophageal glands proper secrete what enzymes via serous cells?
- pepsinogen
- lysozyme
62
Esophageal muscularis externa contains what two layers?
- inner circular
- outer longitudinal
63
Esophageal muscularis externa contains what kind of muscle?
Skeletal and smooth muscle fibers
64
True or false: esophageal muscularis externa contains normal myenteric plexus
True
65
The esophagus contains three _____ regions
Histologically distinct
(pharyngoesophageal sphincter, gastroesophageal spincter, outer tunic)
66
What are the three regions of the esophagus?
- Upper 1/3: Skeletal muscle
- Middle 1/3: Skeletal and Smooth muscle
- Lower 1/3: Smooth muscle
67
Esophagus physiological sphincters
- Pharyngoesophageal (upper esophageal)
- Gastroesophageal (lower esophageal)
68
Retroperitoneal outer tunic of the esophagus is comprised of:
Adventitia
69
Intraperitoneal outer tunic of the esophagus is comprised of:
Serosa
70
The stomach-esophagus junction demonstrates an abrupt transition from _____ to ____
Stratified squamous to simple columnar
71
True or false: esophageal glands proper do not continue into the submucosa of the stomach
False - they do
72
Gastric pits begin to appear at the _____ junction
stomach-esophagus junction
73
The stomach esophagus junction has increased thickness of what tissue layer?
Muscularis externa
74
The stomach is characterized as a ____ structure
Muscular, sac-like
75
Resting stomach volume
50 mL
76
Distended stomach volume
1500 mL
77
____ is the most dilated region of the alimentary canal
Stomach
78
Function of the stomach
Liquifies food through enzymatic digestion and physical maceration
79
The lesser curvature of the stomach is _____ whereas the greater curvature of the stomach is ____
concave; convex
80
What are the anatomically distinct regions of the stomach?
- Cardia
- Fundus
- Body
- Pylorus (pyloric antrum)
81
Narrow region at gastroesophageal junction
Cardia
82
What is the dome-shaped region of the stomach that is frequently filled with gas?
Fundus
83
What is the largest part of the stomach?
Body
84
____ of the stomach makes chyme
Body
85
The pylorus is ___ shaped
Funnel
86
____ culminates at pyloric sphincter
Pylorus
87
What controls the release of chyme into the duodenum?
Pylorus
88
True or false: the anatomically distinct regions of the stomach are the same as the histologically distinct regions
False - they are different
89
Histologically, what regions of the stomach are alike?
Fundus and body
90
The histological regions of the stomach are identified by ____ in the lamina propria
Glands
91
List the histological regions of the stomach
- Cardia
- Fundus
- Pylorus
92
Which of the following is not a histological region of the stomach?
A. Cardia
B. Body
C. Fundus
D. Pylorus
B. Body
93
The gross internal stomach structure contains what components?
- Rugae
- Gastric pits
94
Gastric pits are also known as:
Foveolae
95
Function of rugae in stomach
Allow expansion
96
Rugae are:
Folds of mucosa and submucosa
97
Gastric pits - function
Increase surface area
98
Gastric pits are deeper at:
Pylorus
99
____ gastric glands empty into gastric pit
5-7
100
What are gastric pits?
invaginations of mucosal epithelium continuous with lumen of underlying glands
101
Stomach mucosa is composed of:
- epithelium
- lamina propria
- muscularis mucosa
102
Stomach epithelium consists of what kinds of cells?
Simple columnar
103
In the stomach, _____ secretes alkaline mucus
Surface lining cells
part of epithelium, simple columnar
104
Regenerative cells are found in ____ of the stomach mucosa
Epithelium
105
Gastric glands are contained in what part of the stomach mucosa
Lamina propria (cardiac glands, pyloric glands, fundic glands)
106
True or false: the stomach mucosa contains a layer of muscularis mucosa
True
107
Layers of muscularis mucosa in stomach mucosa
- inner circular
- outer longitudinal
- outermost circular
108
The stomach _____ is rich in blood and lymph vessels
Submucosa
109
The stomach ____ contains a normal compliment of CT cells
Submucosa
110
True or false: the stomach submucosa contains Meissner's submucosal plexus
True
111
Stomach muscularis externa - layers
- inner oblique
- middle circular
- outer longitudinal
112
Stomach glands are named by where the are found, which are:
- cardiac glands
- fundic (gastric) glands
- pyloric glands
113
Stomach glands are found in the ____ of stomach mucosa
Lamina propria
114
Stomach glands structure
Simple or branched tubular
115
Regions of simple branched tubular gland
- Isthmus
- Neck
- Base
116
Fundic gland is also known as:
Gastric gland
117
Fundic glands produce:
- gastric acid
- gastric intrinsic factor
- mucus
118
Fundic gland epithelium contains a variety of cells, which are:
- mucus neck cell
- parietal cell (oxyntic)
- chief cell (zymogenic)
- enteroendocrine cell
119
Which cell is only occasionally found in the gastric gland?
Enteroendocrine cell
120
Surface lining cells of the stomach line:
Surface and gastric pits
121
Surface lining cells secrete:
Thick mucus for protection
122
Nuclei of surface lining cell is ____ located
Basally
123
Apical microvilli and secretory granules are characteristic of ____ cells
Surface lining cells
124
Function of regenerative cell in stomach mucosa
- highly proliferative
- replace all surface and gland cells
125
Regenerative cell - turnover time
5-7 days
126
Mucous neck cell - shape/characteristics
- columnar and irregular in shape
- short microvilli
- basal nuclei
- abundant secretory granules
127
Mucous neck cell secretes:
Soluble mucus for lubrication
128
Where are parietal cells located?
Mostly neck of fundic gland
129
Parietal cell - shape/characteristics
- round to pyramid shaped
- central round nucleus
- eosinophillic cytoplasm
- intracellular canaliculi with microvilli
- tubulovesicular system
- lot of mitochondria
130
What do parietal cells secrete?
- HCl
- Gastric intrinsic factor
131
True or false: Parietal cell is also called oxyntic cell
True
132
Where are chief cells located?
Mostly base of fundic gland
133
General region of the stomach where chief cells found
134
Describe chief cells
- columnar
- basal nuclei
- basophilic from RER
- secretory granules
- short microvilli
135
Chief cells secrete:
- pepsinogen
- gastric lipase
136
Enteroendocrine cells are found at the ___ of fundic gland
Base
137
____ secretes endocrine, paracrine, and neurocrine hormones
Enteroendocrine cells
138
True or false: single type of enteroendocrine cell secretes many types of hormones
False - single type, single hormone
139
____ is considered an APUD cell
Enteroendocrine cell
140
What do APUD cells do?
Take up precursors of amines and decarboxylate them
141
____ has shallow gastric pits
Cardiac mucosa
142
_____ is a highly coiled tubular gland
Cardiac mucosa
143
True or false: there are no chief cells in cardiac mucosa
True
144
What cells are found in cardiac gland?
- mostly surface lining cells
- some mucous neck cells
- few enteroendocrine and parietal cells
145
Cardiac mucosa function mainly to:
Secrete protective mucus
146
Pyloric mucosa has ____ gastric pits
Deep
147
What cells are found in the pyloric gland?
- predominantly mucous neck cells (secrete mucus and lysozyme)
- enteroendocrine cells (G cells) which make gastrin
148
____ are eosinophilic
Parietal cells
149
____ are basophilic
Chief cells
150
Function of small intestine
- digests food
- absorbs nutrients
151
Longest section of GI
Small intestine
152
Layers of small intestine
- mucosa (contains muscularis mucosa)
- submucosa
- muscularis externa
- adventitia/serosa
153
Small intestine mucosa epithelium contains what cell types?
- Surface absorptive cell
- goblet cell
- enteroendocrine cell
- regenerative cell
- paneth cell
- M cells
154
Where are Brunner's glands found?
Submucosa of duodenum
155
Small intestine lamina propria contains:
Crypts of lieberkuhn
156
Structures to increase surface area of small intestine
- Plicae circulares (valves of Kerckring)
- villi
- microvilli
157
What are plicae circulares?
transverse folds of the submucosa and mucosa
158
Plicae circulares increase surface area:
2-3 fold
159
Function of plicae circulares
Decrease velocity of chyme
160
Plicae circulares are most developed in the:
Jejunum
161
Villi are finger like protrusions of the:
Lamina propria
162
Villi increase surface area of small intestine by:
10 fold
163
Microvilli increase surface area of small intestine by:
20 fold
164
What are microvilli?
Modification of the apical plasmalemma of epithelial cells
165
What are crypts of Lieberkuhn?
Invaginations between villi
166
Crypts of lieberkuhn are extended into ___ and contain ____ glands
Lamina propria; simple tubular glands
167
Surface absorptive cell is also called:
Enterocyte
168
Describe surface absorptive cell
- tall columnar
- cover villi and surfaces of intervilli
- brush border with terminal web
169
Function of surface absorptive cell
- terminal digestion
- absorption
170
Goblet cell
- secrete mucinogen
- # increases as you go down GI
171
Enteroendocrine cell of small intestine
- aka DNES
- 1% of cells
172
Paneth cell
- large eosinophilic apical secretory granules
- exocrine cells that secrete lysozyme, defensin, TNFa
173
Unremarkable small intestine submucosa
- dense, irregular, fibroelastic CT
- rich in blood and lymphatic vessels
174
Brunner's glands open up into
Crypts of lieberkuhn
175
Brunner's glands secrete:
- mucus
- bicarbonate rich fluid
- epidermal growth factor
176
Shortest segment of Small intestine
Duodenum
177
Duodenum receives ___ from the liver and ___ from the pancreas via the common bile duct and pancreatic duct
bile; digestive juices
178
Villi of duodenum are:
Broader, taller, more numerous per unit area
179
True or false: there are many goblet cells in the duodenum
False - fewer
180
Villi of jejunum are:
Narrower, shorter, sparser
181
There are more or less goblet cells in the jejunum?
More (less in duodenum)
182
Villi are sparsest, shortest, narrowest in:
Ileum
183
Lamina propria of ileum contains:
Peyer's Patches
184
What are Peyer's patches?
clusters of lymphoid nodules
| in wall of ileum opposite the attachment of mesentery
185
Regions of large intestine
- Cecum (appendix)
- Colon
- rectum
- anus
186
Regions of colon
- ascending
- transverse
- descending
- sigmoid
187
True or false: large intestine does not contain villi or paneth cells
True
188
True or false: large intestine contains crypts of lieberkuhn
True
189
There is an increased or decreased number of goblet cells in the large intestine?
Increased
190
In the large intestine, what parts are unremarkable?
- lamina propria
- muscularis mucosa
- submucosa
191
Rectum resembles the:
Colon
| crypts are deeper and fewer in number
192
Anal canal is ____ ____, 3 cm long
Constricted continuation
| no crypts in distal portion
193
In the rectum and anal canal, the epithelium becomes ____ which becomes keratinized at the ___
stratified squamous; anus
194
Appendix is located at:
diverticulum of cecum
195
Appendix resembles:
colon
196
Appendix has more:
- lymphoid elements
- DNES cells
197
Appendix has small or large diameter?
Smaller
198
Esophageal cardiac glands are found in the _____, whereas esophageal glands proper are found in the _____
Esophageal mucosa (near pharynx/stomach); Submucosa
