3 - GI Tract Flashcards
1
Q
The GI tract is divided into what 4 layers?
A
Mucosa
Submucosa
Muscularis externa
Adventitial layer (serosa)
2
Q
The mucosa is made of what three layers?
A
Epithelium
Lamina propria
Muscularis mucosa
3
Q
The epithelium of the mucosa layer is primarily what?
A
Simple columnar
4
Q
The lamina propria of the GI tract may contain _________, _______, or _________ in its CT
A
Glands
Lymphoid tissue
Blood vessels
5
Q
The lamina propria of the mucosa has what type of CT?
A
Loose areolar
6
Q
The muscularis mucosa is thin ________ and thin _________
A
Circular
Longitudinal
7
Q
What does the muscularis mucosa do?
A
React to the movement of the lumen
8
Q
The innermost layer of the GI tract is what?
A
Mucosa
9
Q
What is the second layer of the GI tract?
A
Submucosa
10
Q
The submucosa of the GI tract is made of __________ CT
A
Dense
11
Q
Submucosa of the GI tract may contain ________ or _________
A
Glands lymphoid tissue
12
Q
The submucosa of the GI tract is ________ than the mucosa layer
A
Stiffer
13
Q
The __________ layer moves and expands
A
Mucosa
14
Q
The 3rd later of the GI tract is made of an inner circular and outer longitudinal layer of smooth muscle - what is it called?
A
Muscularis externa
15
Q
The major source of smooth muscle of the GI tract that is used to move material throughout it is what layer?
A
Muscularis externa
16
Q
The fourth layer of the GI tract that separates the tube from surrounding structures is what layer?
A
Adventitial layer
17
Q
The adventitial layer contains what type of CT?
A
Loose
18
Q
What may you find in the adventitial layer of GI tract?
A
Lots of blood vessels,
lymph vessels,
or adipose tissue
19
Q
Where is the submucosal (Meissner’s) located?
A
Located in the submucosa
20
Q
Where is the myenteric (Auerbach’s) found?
A
Between the layers of muscularis externa
21
Q
What is the myenteric (Auerbachs) nerve plexus for?
A
Innervation of the smooth muscle (muscularis externa)
22
Q
What does the submucosal (Meissners) innervate?
A
Muscularis mucosa
23
Q
Both myenteric and submucosal belong to what nervous system
A
Autonomic
24
Q
The esophagus extends from the ______ to _______
A
Throat to stomach
25
What type of epithelium is found in the mucosa of the esophagus?
Nonkeratinized stratified squamous
26
The lamina propria of the esophagus is _______ CT with _________, __________, and ___________
Loose
Collagen
Elastic fibers
Numerous lymphocytes
27
The esophageal glands are ________ secreting glands
Mucous
28
Muscularis mucosa of the esophagus is __________ __________ muscle with elastic fibers
Longitudinal smooth muscle
29
The submucosa of the esophagus contains ________ CT with _______ and _______ fibers that allow it to expand and contract
Dense
| Collagen and elastic
30
In the submucosa of the esophagus, you will find ______ plexus and _______ secreting glands
Meisnner’s
| Mucous
31
The upper 1/3 of the muscularis externa of the esophagus is _________ muscle
Skeletal
32
The lower 1/3 of the muscularis externa of the esophagus is _________ muscle
Smooth
33
The middle 1/3 of the muscularis externa of the esophagus is _________ muscle
Both skeletal and smooth
34
The adventitia of the esophagus is made of ________ CT that connects the esophagus to surrounding structures
Loose
35
Sphincter at the pharynx and esophagus
Pharyngeoesophageal
36
Sphincter at the stomach and esophagus
Gastroesophageal
37
Esophageal sphincters are ________ and not ________
Function/physiological
| Anatomical/histological
38
What is the function of the stomach?
To mix food and gastric juices
Stores food
Digests food
Some absorption of water, drugs, alcohol
39
What are the regions of the stomach
Cardia
Body & Fundus
Pylorus
40
In the empty stomach, there are folds called what?
Rugae
41
The pyloric sphincter is a _______ sphincter
True
42
What does the polyoric sphincter control
Movement from stomach to small intestine
43
The incisive fissure separated _______ and _______
Body of the stomach and pylorus
44
The ______ extends above the esophagus and is usually just gas
Fundus
45
What is found on the surface epithelium of the stomach?
Gastric pits
46
_______ empty into the gastric pits of the stomach
Branched tubular glands
47
The lamina propria of the stomach is made of_________ CT with _______, ________, and _________
Loose
Lymphoid cells
Macrophages
Mast cells
48
The muscularis mucosa of the stomach has an inner layer of __________ _______ muscle and outer ________ _______ muscle
Circular smooth
| Longitudinal smooth
49
The stomach is lined with what type of epithelium?
Simple columnar with short microvilli and glycocalyx
50
The epithelium of the stomach rests on the basal lamina and is held together by _______ _________
Tight junctions
51
The epithelial cells of the stomach are ________ secreting
Mucous
52
Stomach epithelial cells have a life span of _______ days
3
53
Stomach epithelial cells contain a ________ and little ______
Golgi complex
| RER
54
The nucleus of epithelial cells of the stomach are located where?
The basal portion of the cell
55
The glands of the fundus of the stomach are what?
Simple branched tubular glands
56
What are the 4 cell types found in the fundus?
Chief cells
Parietal Cells
Mucous neck cells
APUD cells
57
Simple cuboidal cells in the lower 1/3 of the branched tubular gland of the fundus
Chief cells
58
Chief cells contain ________ in their course granules to break down ________
Pepsinogen
| Amino acids
59
Large spherical wedges between chief cells are ________ cells
Parietal
60
Parietal cells in the fundus secrete what?
HCl and gastric intrinsic factor
61
Parietal cells of the fundus are intensely ______ with _____ nuclei
Acidophilic
| 1 or 2
62
The anal canal represents the end of the ___________ epithelium and the beginning of ________ epithelium
Simple columnar
| Stratified squamous
63
The mucosa in the anal canal forms __________ ____, which are the rectal columns
Longitudinal folds are the rectal columns
64
Lamina propria in the anal canal has ________
Very large veins
65
In the anal canal the muscularis mucosa becomes ________
Incomplete
66
What is the function of the large intestine?
Water reabsorption and mucous production
67
The water absorption in the large intestine is passive as water flows with _____
Na+
68
What is the mucosa of the large intestine consist of?
Smooth with NO folds and LACKS villi
69
The lamina propria in the large intestine has ______
Lamina propria has many lymphoid cells
70
What are the crypts in the large intestine densely packed with?
Many goblet cells
71
Describe the muscularis mucosa of the large intestine
Well developed with inner circular and outer longitudinal smooth muscle layers
72
The submucosa in the large intestine is _________
Is loosely arranged with fat and no glands
73
The muscularis externa of the large intestine has a complete layer of ___________ muscle and an incomplete layer of _______________ muscle
Complete layer of circular smooth muscle and an incomplete layer of longitudinal smooth muscle
74
What forms the tenia coli of the large intestine?
Circular layer of smooth muscle and incomplete layer of longitudinal smooth muscle
75
The serosa of the large intestine has ________ in it
Adipose tissue
76
_________ is a blind evagination of the cecum
Appendix
77
The appendix has mucosal crypts that have ________
Lymphoid tissue
78
The epithelium of the appendix is ________ with a few goblet cells
Absorptive
79
What cells are located at the base of the crypts in the appendix?
Paneth cells and APUD cells
80
What is the submucosa like in the appendix?
Thick with adipose tissue present
81
The muscularis of the appendix is _______ with no _______
Normal with no tenia coli
82
What is present in the appendix that is important for B cell production?
GALT
83
The appendix has no _____ but does have ______
Villi but does have Crypts of Liberkahn
84
The jejunoileum has the same pattern as the duodenum but there is an increase in the number of ______ and ______
Goblet cells and lymphoid tissue
85
Does the jejunoileum have Brunner’s glands?
NO there are no brunners glands in the jejunoileum
86
In the jejunoileum, the lamina propria is made up of loose CT with ____________ tissue that form the core of the ______
Lymphoid tissue that forms the core of the villi
87
What is the muscularis mucosa made up of in the jejunoileum
Made up of an inner circular layer and outer longitudinal layer of smooth muscle
88
The submucosa of the jejunoileum is a dense connective tissue with _______ fibers
Elastic fibers
89
The lymphoid nodules make up the __________, which are made up of GALT and covered by M-cells
Peyers patches
90
What are peyers patches made up of and what are they covered by?
GALT and covered by M cells
91
The muscularis externa of the jejunoileum is made up of ________ and _______ smooth muscle
Inner circular and outer longitudinal
92
What is the duodenum’s mucosa epithelium composed of?
Simple columnar epithelium arranged in the pattern of the villi and crypts of Lieberkuhn
93
What are the mucous glands called that are located in the submucosa of the duodenum?
Brunner’s glands
94
_______ glands in the duodenum’s submucosa secrete an alkaline mucous that has a pH of 8.1- 9.9
Brunner’s glands
95
The duodenum has a typical _______ and ______
Muscularis externa and adventitia
96
The villi contain what two cell types on their surface?
Absorptive cells and APUD cells
97
The villi’s lamina propria contains ________ for the absorption of fats, _______ for the absorption of carbs and proteins, and _______ for the rhythmic movement of the villi
Lymphatics
Blood vessels
Smooth muscle
98
What is the function of villi?
Absorption
99
________ cells are specialized epithelial cells that are found over the lymphoid nodules of peyers patches
M (microfold) cells
100
What are M cells characterized by?
Numerous invaginations that form pits for lymphocytes and macrophages
101
M cells basement membranes are ______ and can ________ Ag and transport them to the lymphocytes and macrophages
Discontinuous
| Endocytose Ags
102
Do M cells contain Villi?
NO
103
______ cells are mucous secreting cells with mucinogen granules in the apex of the cell long with the RER and golgi complex
Goblet cells
104
______ cells are interspersed among the absorptive cells and increase in number fro proximal to distal
Goblet cells
105
Which cell in the fundus is located in the neck of the gland, interspersed among parietal cells
Mucous neck cells
106
Mucous neck cells produce what?
Acidic mucous
107
Mucous neck cells have ________ basal nuclei and ________ _______ granules in their cytoplasm
Flattened
| Large spherical
108
Mucous neck cells secrete mucous for what?
Protection of the stomach from HCl & pepsin
109
APUD cells have ______ secretory granules
Basal
110
The golgi complex of the APUD cells are _________
Supranuclear
111
APUD cells have a _______ apical region that reaches the lumen with microvilli
Narrow
112
What is the function of APUD cells?
Secrete hormones
113
Cardia are composed of ________ cells and a few ________ cells
Mucous
| APUD
114
Cardia of the stomach have __________ gastric pits
Very shallow
115
What is the epithelium of cardia of the stomach?
Nonkeratinized stratified squamous
116
The transition from esophagus to cardia of stomach is marked by what?
Change in epithelium
117
You will see unorganized _______ in the cardia of the stomach
Lymphocytes
118
The pylorus of the stomach have ________ gastric pits
Deeper
119
Glands of the pylorus of the stomach are ________ ________ tubular glands
Simple branched
120
Pylorus glands of the stomach are made of _________ cells
Mucous neck
121
What is the function of the pylorus of the stomach?
Protect the pylorus from autodigestion
122
Submucosa of the stomach is made of ________ CT with no lymphoid elements
Dense irregular
123
The submucosa of the stomach is rich in ________, _______, and ________
Mast cells
Lymphocytes
Eosinophils
124
The outer layer of the muscularis external of the stomach is made of what?
longitudinal smooth muscle - complete
125
The middle layer of the muscularis external of the stomach is made of what?
Circular smooth muscle - complete
126
The inner layer of the muscularis external of the stomach is made of what?
Oblique layer of smooth muscle - not complete
127
What are the three functions of the small intestine?
Digestion of food
Selective absorption
Endocrine function
128
What are the histological divisions of the small intestine?
```
Duodenum
Jejunum (jejunum and ilium are the same histologically)
```
129
The small intestine has _________, _________, and ________ to increase the surface area for absorption
Plicae semilunaris
Vilii
Microvilli
130
Permanent folds that involve the mucosa and submucosa
Plicae semilunaris
131
Projections form the mucosa
Villi
132
Cytoplasmic extensions of the cell
Microvilli
133
The small intestine what type of epithelium?
Simple columnar
134
You will find __________ in the loose CT of the lamina of the small intestine
Smooth muscle
135
Crypts of lieberkuhn open to the what?
Base of the villi
136
Crypts of lieberkuhn contain what 4 cells?
Absorptive cells
Paneth cells
Goblet cells
M(microfold) cells
137
Absorptive cells are what type of cells?
Simple columnar
138
What are the components of an absorptive cell?
```
Basal ovoid nuclei
Mitochondria
Supranuclear golgi
SER
Microvilli (aka brush) border
Actin protein core
```
139
Absorptive cells are held together by what?
Tight junctions and desmosomes
140
How often are absorptive cells replaces?
Every 1-2 days
141
Paneer cells are located where?
In the basal crypts
142
_______ cells are pyramidal in shape with round basal nuclei (found in crypts of lieberkuhn)
Paneth
143
What are the components of paneth cells?
Eosinophilic granules
RER
Golgi
Zinc granules
144
Which crypts of lieberkuhn cells are used for heavy metal absorption?
Paneth cells
145
The granules in paneth cells contain
IgA & IgG for the regulation of the intestinal flora and
Lysozyme for the breakdown of bacterial walls
