E5 Ch. 23 Flashcards
(133 cards)
1
Q
what 2 groups are the organs of the digestive system divided into
A
alimentary canal and accessory digestive organs
2
Q
list the organs that belong to the alimentary canal
A
mouth, pharynx, esophagus, stomach, small intestine, and large intestine
3
Q
list the accessory digestive organs
A
teeth, tongue, gallbladder, salivary glands, liver, and pancreas
4
Q
how are accessory organs and alimentary canals connected
A
via ducts
5
Q
list the 4 lines that divide the abdominal wall
A
midclavicular (vertical lines), subcostal plane (superior horizontal), transtubercular plane (inferior horizontal
6
Q
peritoneum
A
serious membrane
7
Q
visceral peritoneum
A
surrounds digestive organs
8
Q
parietal peritoneum
A
lines body wall
9
Q
peritoneal cavity
A
slitlike potential space
10
Q
what is a mesentery and its function
A
double layer of peritoneum; holds organs in place, fat storage, provide route for circulatory vessels/nerves
11
Q
name the structures found in the ventral mesenteries
A
falciform ligament and lesser omentum
12
Q
function of falciform ligament
A
binds anterior part of liver to anterior abdominal wall
13
Q
function of lesser omentum
A
attaches liver to lesser curvature of stomach
14
Q
list the dorsal mesenteries
A
greater omentum, transverse mesocolon, and sigmoid mesocolon
15
Q
function of greater omentum
A
connects greater curvature of stomach to posterior abdominal wall, “fatty apron”
16
Q
function of transverse mesocolon
A
holds transverse colon in place
17
Q
function of sigmoid mesocolon
A
connects sigmoid colon to posterior pelvic wall
18
Q
retroperitoneal organs
A
behind the peritoneum
19
Q
peritoneal organs
A
digestive organs that keep their mesentery
20
Q
where does ingestion occur
A
mouth
21
Q
propulsion
A
movement of food
22
Q
peristalsis
A
major means of propulsion; adjacent segments of alimentary canal relax and contract
23
Q
mechanical breakdown
A
preps food for chemical digestion; chewing, churning food in stomach, and segmentation
24
Q
what is segmentation
A
rhythmic local constrictions of intestine; mixes food w/ digestive juices
25
what is chemical digestion and where does it occur
complex molecules broken down to chemical components; mouth, stomach, and small intestine
26
absorption
transport of digested nutrients
27
defecation
elimination of indigestible substances as feces
28
list the 4 layers of the alimentary canal
mucosa, submucosa, muscularis externa, and serosa
29
what are the sublayers of the mucosa
epithelium, lamina propria, muscularis mucosae
30
what structures are found in the submucosa
blood and lymphatic vessels, and nerve fibers
31
name the 2 layers that make up the muscularis externa
circular muscularis (inner layer) and longitudinal muscularis (outer layer)
32
what is the serosa
the visceral peritoneum
33
where is smooth muscle found
walls of viscera
34
describe the longitudinal layer
parallell to long axis of organ
35
describe the circular layer
deeper layer, fibers run around circumference of organ
36
what is the mechanism of contraction with smooth muscles
myofilaments operate by interaction w/ cytoskeleton, dense bodies correspond to Z-discs of skeletal muscle; sliding myofilaments shorten muscle cells by pulling on ctoskeleton
37
what is the rate of contraction with smooth muscles
contraction slow and sustained (30X longer to contract/relax), resistant to fatigue, low energy requirements
38
innervation of smooth muscles via
ANS
39
single-unit innervation
few fibers per sheet innervated; sheet of smooth muscle contracts as a unit
40
multiunit innervation
each smooth muscle cell innervated (e.g. iris of eye and arrector pili muscles)
41
where is the myenteric nerve plexus lie and what does it control
leis b/t circular and longitudinal muscularis; controls peristalsis and segmentation
42
where is the submucosal nerve plexus located and function
lies in submucosa; signals glands to secrete
43
list the boundaries of the mouth (oral cavity)
lips (anteriorly), cheeks (laterally), palate (superiorly), tongue (inferiorly), fauces of oropharynx (posteriorly)
44
what type of cells are found in the mucosal layer of the oral cavity
stratified squamous epi
45
what muscles are the lips and cheeks formed from
orbicularis oris and buccinator
46
function of labial fernulum
connects lips to gum
47
name the boundaries of the fauces
palatoglossal and palatopharyngeal arches
48
function of the tongue
grips food, repositions, helps form some consonants
49
function of the lingual frenulum
secures tongue to floor of mouth
50
where are intrinsic and extrinsic muscles of the tongue located
intrinsic muscles- w/in tongue
extrinsic muscles-external to tongue
51
list the types of tongue papillae
filiform (no taste buds), fungiform, and vallet papillae
52
what is the sulcus terminalis
marks border b/t mouth and pharynx
53
where does the posterior 1/3 of the tongue lie
in oropharynx; lined w/ lingual tonsil
54
how many deciduous teeth do we have and when do they appear
20; 6 months of age
55
how many permanent teeth de we have and when do they appear
32, most erupt by end of adolescence
56
what is the dental formula
shorthand; formula for adult dentition indicates number and position of teeth (e.g. 2K, 1C, 2P, 3M
57
what type of innervation is in the upper teeth
superior alveolar nerves branching from maxillary division of CN V
58
what type of innervation is in the lower teeth
inferior alveolar nerves branching from mandibular branch of CN V
59
crown
exposed surface of tooth
60
root
in tooth socket
61
what is the outer layer of the tooth
enamel
62
dentin
underlies enamel
63
pulp cavity
center of tooth
64
what type of cells are found in parotid glands
only serious cells
65
where are submandibular glands located
lie along medial surface of mandible
66
where are sublingual glands located and why type of cells do they contain
lie in floor or oral cavity, contain primarily mucous cells
67
what type of epi are found in the oropharynx and laryngophary x
stratified squamous epi
68
function of the cardiac sphincter
closes lumen to prevent stomach acid from entering esophagus
69
what type of tissue is found in the esophagus
stratified squamous epi
70
what type of muscle is found in the esophagus
mixture of skeletal and smooth (middle 1/3), smooth (inferior 1/3)
71
the stomach is the site for what
where food is churned into chyme
72
what type of chemical does the stomach secret
pepsin; beings protein digestion
73
how long does food typically remain in the stomach
approximately 4 hours
74
name the 3 muscularis layers of the stomach
circular, longitudinal, and oblique layers
75
what type of tissue is found in the stomach
simple columnar epi
76
what is found in the mucosa of the stomach
gastric pits; gastric glands deep to gastric pits
77
list the gastric glands of the fundus and body regions of the stomach
mucous neck cells, parietal (oxyntic) cells, and chief (zymogenic) cells
78
what do mucous neck cells secrete
special mucus
79
what do parietal (oxyntic) cells secrete
hydrochloric acid and gastric intrinsic factor
80
wha do chief (zymogenic) cells secrete
pepsinogen; activated into pepsin when encounters acid in gastric glands
81
what organ is the longest portion of the alimentary canal
small intestine
82
what are the 3 subdivisions of the small intestine
duodenum, jejunum, and ileum
83
what type of innervations are in the small intestine
parasympathetic fibers from vagus nerves, sympathetic from thoracic splanchnic nerves
84
what chemicals does the duodenum receive
digestive enzymes and bile
85
what structures enter the duodenum
main pancreatic and common bile duct; sphincters control entry of bile and pancreatic juices
86
what are some modifications for absorption found in the small intestine
circular folds, billi, and microvilli
87
what are circular folds
transverse ridges of mucosa and submucosa
88
what are villi
fingerlike projections of mucosa, covered w/ simple columnar epi
89
what are microvilli
further increase surface area for absorption
90
function of absorptive enterocytes
uptake digested nutrients
91
function of goblet cells
secrete mucus that lubricates chyme
92
function of enteroendocrine cells
secrete hormones
93
intestinal crypts
epi cells secrete intestinal juice
94
functions of the large intestine
small amount of digestion by bacteria, main function- absorb water and electrolytes
95
list the subdivisions of the large intestine
cecum, appendix, colon, rectum, anal canal
96
list the special features found on the large intestine
teniae coli, haustra, epiploic appendages
97
teniae coli
thickening of longitudinal muscularis
98
haustra
puckering created by teniae coli
99
epiploic appendages
fat-filled pouches of visceral peritoneum
100
cecum
blind pouch, beginning of large intestine
101
what does the appendix contain and function
contains lymphoid tissue; neutralizes pathogens
102
what is the anal canal and what type of tissue lines it
last subdivision of large intestine, lines w/ stratified squamous epi
103
name the artery that supplies the first half of the large intestine
superior mesenteric artery
104
innervations of the first half of large intestine
sympathetic- superior mesenteric and celiac ganglia
parasympathetic- vagus nerve
105
name the artery that supplies the distal half of large intestine
inferior mesenteric artery
106
innervations of the distal half of large intestine
sympathetic- inferior mesenteric and hypogastric plexuses
parasympathetic- pelvic splanchnic nerves
107
type of tissue found in large intestine
simple columnar epithelial tissue, becomes stratified squamous epi at anal canal
108
what is the largest gland in the body
liver
109
what is the digestive function the liver
bile production
110
hepatocyte
functional cells of liver
111
what is the portal triad of the liver composed of
bile duct tributary, branch of hepatic portal vein, branch of hepatic artery
112
function of hepatic macrophages
destroy bacteria
113
function of gallbladder
stores and concentrates bile which emulsifies fats
114
where does the gallbladder expel bile into
duodenum
115
where and when is cholecystokinin released
from enteroendocrine cells in response to fatty chyme
116
what type of functions does the pancreas carry out
both exocrine and endocrine functions
117
what is the endocrine function of the pancreas
produce insulin and glucagon, regulates blood sugar
118
what is the exocrine function of the pancreas
produces most enzymes that digest food in small intestine
119
what structures form the hepatopancreatic ampulla
area where main pancreatic duct joints bile duct; empties into duodenum
120
where does the pancreas receives arterial supply from
hepatic, splenic, and superior mesenteric arteries
121
what are the pancreas exocrine functions
acinar cells make, store, and secrete pancreatic enzymes which are activated in the duodenum
122
what are peptic ulcers
erosions of the mucosa of a region of the alimentary canal
123
where do gastric ulcers occur
in pyloric region of stomach
124
where do duodenal ulcers occur
in duodenum of small intestine
125
name and describe the pathogen that causes peptic ulcers
Helicobacter pylori; acid-resistant, binds to gastric epi, induces over secretion of acid and inflammation
126
what are the 2 types of intestinal obstructions
mechanical and nonmechanical
127
list the types of mechanical obstructions
adhesions, tumors, or foreign objects
128
what are some causes of non-mechanical obstructions
halt in peristalsis; trauma, intestines touched during surgery
129
what is fnflammatory bowel disease and list the 2 types
inflammation of intestinal wall; Crohn's disease and Ulceratice colitis
130
list the major types of viral hepatitis and what are some general symptoms
A, B, C and G; jundice and flulike symptoms
131
describe how cystic fibrosis affects the pancreas
pancreatic ducts become blocked w/ mucus, which prevent pancreatic juices from entering small intestine, leads to malabsorption of fats and other nutrients
132
during embryonic development, when is the alimentary canal formed and what does it enclose
week 3, encloses tubular portion of yolk sac
133
what is the vitelline duct during embryonic development
landmark dividing into 3 regions: foregut, midgut, an hindgut
