Digestive System (7) Flashcards
(112 cards)
1
Q
What are 8 functions of the digestive system?
A
- ingestion
- mastication
- secretion
- absorption
- elimination
- motility
- hormone release
- chemical digestion
2
Q
Where is the masticatory mucosa found?
A
gingiva and hard palate
3
Q
What type of surface epithelium is found in the masticatory mucosa?
A
keratinized or prakeratinized stratified squamous
4
Q
What is special about the superficial cells of parakeratinized stratified squamous epi?
A
they keep their nuclei
5
Q
What are the 2 parts of the lamina propria in the masticatory mucosa?
A
1. papillary layer >thick loose CT >BV, nerves, sensory, meissner's 2. reticular layer >more dense CT
6
Q
Where is lining mucosa found?
A
soft palate, underside of tongue, floor of mouth, cheeks and lips
7
Q
What surface epithelium is generally found on lining mucosa?
A
nonkeratinized stratified squamous epi
occasionally prekaratinized
8
Q
What type of surface epi is found on the vermilian zone?
A
keratinized stratified squamous epi
9
Q
Which areas are thicker, ares of non-keratinized or areas of keratinized stratified squamous?
A
non-keratinized
10
Q
What are characteristics of the lamina propria in lining mucosa?
A
loose CT with BV and nerves
11
Q
What are characteristics of the submucosa in lining mucosa?
A
- more dense CT
- can have minor salivary glands, sebaceous glands (mouth corners)
- can have larger BV and nerves
12
Q
Where is specialized mucosa found?
A
dorsal surface of tongue
13
Q
What type of surface epi is found on filiform papillae?
A
keratinized stratified squamous
14
Q
What type of surface epi is found on the other papillae (besides filiform)?
A
stratified squamous
15
Q
What is the general function of the specialized mucosa (papillae)?
A
- move food
2. taste
16
Q
What is the arrangement of the mucosa in the tongue?
A
thicker dorsally
thinner and smoother posteriorly
17
Q
What is the surface epi of the tongue mucosa?
A
- keratinized on filiform
2. stratified on others
18
Q
Small salivary (von Ebner) glandsd are associated with which papillae?
A
vallate
19
Q
What is the function o von Ebner glands?
A
produce serous fluid to cleanse the taste buds on vallate papillae
20
Q
Which papillae have taste buds?
A
all except filiform papillae
21
Q
What are characteristics of the lamina propria in the mucosa of the tongue?
A
loose CT; adipose possble
22
Q
What does the submucosa of the tongue mucosa contain?
A
lingual salivary glands
23
Q
What is one of the main characteristics of the intrinsic tongue muscles?
A
- no external attachment
- skeletal muscle
24
Q
What is the function of the intrinsic tongue muscles?
A
change tongue shape
25
What is lost after tooth eruption?
ameloblasts
26
What is the function of ameloblasts?
produce enamel
27
What is the hardest substance in the body?
enamel
28
What is enamel made up of?
interlinked enamel rods
29
Can we make more enamel after tooth eruption?
no
| ameloblasts are lost after tooth eruption
30
What is the make up dentin?
thin dentinal tubules containing nerves and cell processes of odontoblasts
31
What is the precursor to dentin before mineralization?
predentin
32
What is the function of odontoblasts?
- repair and produce dentin
| - maintain dentin
33
What are odontoblasts?
columnar cells lining pulp cavity
34
What is dental papilla
CT with many BV and nerves
35
What can dental papilla also be called?
dental pulp
36
T/F: extensive inflammation in the dental papilla can be problematic?
true
37
Which is the largest salivary gland?
parotid gland
38
What products does the parotid gland make?
1. salivary amylase
2. lysosome
3. secretory IgA
39
What is the function of salivary amylase?
break down carbs
40
What type of gland is the submandibular gland?
mixed gland
41
What is the major product of the submandibular gland?
serous products (80-90%)
42
Which gland is the smallest salivary gland?
sublingual gland
43
What is the major product of the sublingual gland?
mucus products (80%)
44
Where do all serous products come from in the sublingual gland?
demilunes
45
Which gland is 100% serous producing?
parotid gland
46
In general what is the muscularis mucosae made up of in the digestive tract?
smooth muscle
47
What is the function of submucosal plexus (Meissner)?
influence the mucosa
48
What is the fiber orientation of the muscularis externa in the digestive tract?
normal pattern: inner circular, outer longitudinal
49
What is the function of the myenteric plexus (Auerbach)?
influence muscularis externa
50
What is the surface eipthelium of the esophageal mucosa?
stratified surface squamous epi
51
What type of glands are found in the esophageal lamina propria?
esophageal cardiac glands
52
What is the function of the esophageal cardiac glands?
produce neutral mucus to protect esophageal epithelium
53
What glands are found in the esophageal submucosa?
esophageal glands (proper)
54
What is the function of the esophageal glands?
produce slightly acidic mucus to lubricate the movement of food
55
What is the arrangement of the esophageal muscularis externa?
normal pattern: inner circular and outer longitudinal
56
What type of muscle is seen in the upper 1/3 of the esophagus?
all skeletal muscle
57
What type of muscle is seen in the middle 1/3 of the esophagus?
mixture of smooth and skeletal muscle
58
What type of muscle is seen in the lower 1/3 of the esophagus?
all smooth muscle
59
What is the last 1-2 inches of the esophagus (after diaphragm) made up of?
serosa
60
What type of sphincters are the pharyngoesophageal and gastroesophageal sphincters?
physiological sphincters
61
Where is the pharyngoesohageal sphincter found?
between the oropharynx and esophagus
62
Where is the gastroesophageal sphincter found?
between esophagus and stomach
63
What are 2 main characteristics of physiological sphincters?
1. no thickening of circular muscle in muscularis externa
| 2. pressure gradient aids movement
64
What is the primary function of the stomach?
storage
65
What are the other functions of the stomach?
1. continue digestion of carbs
| 2. nutrient breakdown: primarily chemical
66
What type of surface epithelium is seen in the stomach mucosa?
simple columnar epi
67
What is another term for surface mucous cells?
surface lining cells
68
What is the function of the surface mucous cells?
1. produce thick visible mucus
| 2. secrete bicarbonate ions
69
In what layer are the arteriovenous anastomosis found in the stomach?
submucosa
70
What is the function of the arteriovenous anastomosis in the stomach?
shut down activity and secretion FAST
71
What is the function of the submucosal plexus?
influence mucosa
| example: secretion, blood flow, muscle contractions
72
Which muscle layer in the muscularis externa is sometimes present?
innermost oblique
73
Which muscle layer in the muscularis externa is well developed?
middle circular
74
Which muscle layer in the muscularis externa is present, but thin?
outer longitudinal
75
What is the function of the myenteric plexus?
stimulate muscularis externa
76
Where is the myenteric plexus found?
between the circular and longitudinal layers
77
What types of cells are found in the cardiac region of the stomach?
- surface mucous
- neck mucous
- few DNES
- parietal cells
- NO CHIEF CELLS
78
What do surface mucous cells in the isthmus produce?
thick visible mucus that traps bicarbonate iions
79
What is the function of the surface mucous cells in the isthmus?
protect mucosa from auto-digestion and the rougher components of chyme
80
What is another term for DNES cells?
enteroendocrine cells
81
What is the product and function of Type G DNES cells?
produces gastrin the stimulates HCl and pepsinogen secretion, gastric motility, adn regenerative cells in body of stomach
82
What is the function of the neck mucous cells?
produce soluble, less alkaline mucus that lubricate gastric contents
83
What is the function of the regenerative cells in the neck of the gastric gland?
replace all cell types
84
What does the parietal cells in the neck of the gastric gland produce?
- HCl
| - gastric intrinsic factor
85
What is the function of gastric intrinsic factor?
necessary for vitamin B12 absorption
86
What do the chief cells produce?
- pepsinogen* (break down protein)
| - gastric lipase (break down fats)
87
What are some characteristics of an anatomical sphincter?
1. well developed inner circular layer of muscle in ME
| 2. inner circular layer in ME can be independently controlled
88
What type of sphincter is the pyloric sphincter?
anatomical sphincter
89
What type of epithelium is seen in the small intestine?
simple columnar
90
What is another term for the surface absorptive cells?
enterocytes
91
What are the functions of the surface absorptive cells in the SI?
1. absorb water and nutrients
| 2. terminal digestion in glycocalyx
92
What are the products of DNES cells in the small intestine?
CCK
GIP
Secretin
93
What are unique cells in the small intestine?
paneth cells
94
Where are paneth cells located?
at the base of the crypts (intestinal glands)
95
What do paneth cells produce?
lysosome
96
Where are M cells found?
in ileum epithelium over Peyer's Patches
97
What is the general function of M cells?
promote humoral immunity
| important in maintaining appropriate gut flora
98
What are lacteals?
lymphatic capillaries found in the villus core of the LP
99
What is the function of lacteals?
lipid absorption
100
What do the Brunner glands primarily produce?
alkaline mucus which neutralizes chyme
101
What is a secondary product that Brunner glands make?
urogastrone which inhibits HCL secretion
102
What type of sphincter is the ileocecal valve?
anatomical and physiological sphincter
103
What are 3 important factors of the appendix?
1. short crypts
2. no villi
3. no paneth cells
104
What are notable structures in the submucosa of the appendix?
numerous lymph nodes
105
What are the 2 functions of the appendix?
1. humoral immunity
| 2. reservoir for good bacteria
106
What is the primary function of the colon?
water absorption
107
What type of epi is in the colon?
simple columnar
108
What are the absorptive cells in the colon?
colonocytes
109
Does the colon have villi or paneth cells?
no
110
Is the pattern of the ME in the colon normal?
no - outer longitudinal muscle gathered into bands = taniae coli
111
Does the ascending and descending colons have adventitia or serosa?
mainly adventitia with some serosa
112
Does the transverse and sigmoid colons have adventitia or serosa?
mostly serosa; mixed
