GI System Flashcards
1
Q
What are the two groups of organs in the GI system
A
Alimentary and accessory
2
Q
What is the order of the alimentary organs (must in order)
A
Mouth, pharynx, esophagus, stomach, small intestine, large intestine, anus
3
Q
What are the accessory organs and what do they do
A
Liver, pancreas, gallbladder, saliva glands
they produce secretions that break down foods
4
Q
what are the 6 processes of digestion
A
digestion, propulsion, mechanical breakdown, chemical breakdown(digestion), absorption, defecation
5
Q
What is peristalsis
A
Process that allows food to move(forward and down), Think of waves of contraction
6
Q
What is segmentation
A
A form of mechanical breakdown in which food in the intestines gets mixed around with digestive juices
7
Q
What is mastication
A
Chewing
8
Q
What is the peritoneum and what does it consist of
A
A serous membrane of the abdominal cavity
it consists of the visceral peritoneum and the parietal peritoneum
9
Q
What is the membrane that touches the surface of most digestive organs (faces the organs)
A
The Visceral peritoneum
10
Q
What is the membrane that lines the body wall
A
The parietal peritoneum
11
Q
What is the peritoneal cavity
A
A fluid filled space between the two peritoneums which lubricates mobile organs
12
Q
what is the mesentery and its function
A
it is a double layer of peritoneum in which the layers are fused to the back
It provides routes for blood vessels, lymphatics, and nerves
13
Q
what is peritonitis
A
inflammation of peritoneum
can be caused by an ulcer piercing wound, or ruptured appendix
can be fatal
treat with huge amount of anitbiotics and debris removal
14
Q
What are the four basic layers of all the GI tract
(Must be in order of deep to superficial)
A
Mucosa, submucosa, muscularis externa, serosa
15
Q
Where is the mucosa found and what are its functions
A
Inner most layer that lines the lumen
it secretes mucous, digestive enzymes, and hormones
absorbs end products of digestion
and protects against disease
16
Q
Where is the sub mucosa and what are its functions
A
exterior to mucosa
contains blood vessles and lymph vessels, and submucosal nerve plexus that supply surrounding GI tracts tissues
Abundant with elastic tissues that help organs regain shape (stomach stretch)
17
Q
What does the muscularis externa layer do
A
layer responsible for peristalsis and segmentation
circular muscles called sphincters
18
Q
Where is the serosa and what is it made of
A
It is the outermost layer which is made of the visceral peritoneum
19
Q
Where are sphincters usually found
A
Where different organs connect
20
Q
What is the enteric nervous system
A
Nervous system dedicated to the GI tract
contains more neurons in spinal cord
21
Q
What regulates the glands and smooth muscle in the mucosa (think peristalsis and segmentation)
A
The submucosal nerve plexus
22
Q
What controls GI tract motility
A
Myenteric nerve plexus
23
Q
What is the Buccal cavity
A
the mouth
24
Q
What cells line the mouth and why
A
Stratified squamous (tough cells to resist abrasion)
25
What is the hard palate made of and where is it
Bone and more anteriorly
26
What is the soft palate and what does it do
Mostly made of skeletal muscle, it closes off the nasopharynx during swallowing
27
What is the uvula
A finger-like projection that faces downward from the free edge of the soft palate
28
What is a bolus
A semi-liquid mass of chewed up food that we swallow
29
what is the lingual frenulum
it attaches the tongue to the floor of the mouth
30
what is ankyloglossia and what are complications associated
A congenital condition where babies are born with a short frenulum
causes speech impairment and prevents feeding as an infant
31
*Where is the parotid gland anatomically*
(need to know)
anterior to ear and external to masseter muscle
32
*Where is the submandibular gland*
(need to know)
it is medial to the body of the mandible
33
*Where is the sublingual gland*
(need to know)
anterior to submandibular gland under tongue
34
What are the functions of saliva
cleanses mouth
dissolves food chemicals for taste
moistens food to make bolus
begins breakdown of starch with salivary amylase
35
What is xerostomia and what are some complications
Chronic dry mouth caused by saliva not being produced
lead to difficulty chewing and swallowing as well as oral infections like ulcers and canker sores
36
What can cause xerostomia
Common meds, HIV/AIDS, Diabetes, Sjorgen syndrome (autoimmune attacks salivary glands)
37
What is lingual lipase
Enzyme that breaks down fats
38
What is primary dentition
The first set of teeth found in babies (20)
39
how many teeth is normal for an adult
32(emerge at 6-12)
40
Which area of the pharynx is not involved in digestion
nasopharynx
41
What is the esophagus primary function and what does it not do
Its main function is peristalsis of food and drink into the stomach
it does not preform segmentation
42
What is the point of the esophagus that pierces the diaphragm
esophageal hiatus
43
what is the cardial orifice
Where the esophagus joins the stomach
44
Where is the cardiac sphincter and what does it do
It is found in the junction between the esophagus and the stomach
it is closed when food is not being swallowed to prevent acid reflux
45
What is GERD (gastroespohageal reflux disease)
chronic acid reflux
46
What can cause GERD/acid reflux
Hiatal hernia
obesity, pregnancy, alcohol, etc
47
What is a hiatal hernia
A structural abnormality where the stomach protrudes above the diaphragm
can lead to cancer and ulcers
48
what is another word for swallowing
Deglutition
49
What are the 2 phases of swallowing
Buccal and pharyngeal-esophageal phase
50
What is the buccal phase of swallowing
The voluntary movement of the tongue to swallow
51
What is the pharyngeal-esophageal phase of swallowing
INVOLUNTARY phase of swallowing that involves the vagus nerve
*controlled by swallowing center in medulla and pons*
52
What is the function of the stomach
Storage tank for food and starter of chemical breakdown of protein
53
Where does the food bolus get converted into chyme
The stomach
54
What are the four major regions of the stomach
Body, cardial, fundus, pylorus
55
Which region of the stomach surrounds the cardial orifice
Cardial
56
Which region of the stomach is dome shaped beneath the diaphragm
The fundus
57
What region of the stomach is the mid portion
The body
58
What region of the stomach is the lower end that joins with the duodenum of small intestines
the pylorus
59
Where is the pyloric sphincter and what does it do
It is between the duodenum and the pylorus of the stomach
it controls when stoma contents enter the small intestines
60
What is the convex lateral surface of the stomach
the greater curvature
61
What is the concave medial surface of the stomach
The lesser curvature
62
What are the secretory cells of the stomach in the fundus
mucous cells
parietal cells
chief cells
enteroendocrine cells
63
What produces mucous and why is it important
mucous cells
important because they contain buffers to keep stomach acid from eating through the stomach
64
What stomach cells produce HCL
Parietal cells
65
Why is stomach acid important
it activates pepsin, denatures proteins and kills many bacteria and viruses
66
What is intrinsic factor and what produces it
Intrinsic factor allows you to absorb b12 in the small intestine
it is produced by the parietal cells of the stomachq
67
lacking which stomach cell is linked to pernicious anemia and why
Parietal cells because they make intrinsic factor which allows vitamin b12 to be absorbed which is essential to the production of RBCS
68
What is pepsinogen
Inactivated pepsin
pepsin begins protein digestion
69
What produces pepsinogen
Chief cells
70
What is a lipase
an enzyme that digests lipids
71
What produces lipases in the stomach
Chief cells
72
What does serotonin do
promotes peristalsis, segmentation, and inflammation
73
What does gastrin do
promotes GI motility and acid release
74
what does histamine do
regulates acid secretion
75
what does somatostatin do
reduces secretions and motility
76
Which digestive chemical messenger does not influence the movement of food
Histamine
77
What hormones do the enteroendocrine cells release
somatostatin, histamine, serotonin, gastrin
78
what are three important characteristics of stomach mucosal barrier
sodium bicarbonate (buffer) layer, tight junctions between epithelial cells to prevent leakage, damaged epithelial cells replaced very rapidly
79
What is gastritis
Inflammation of the stomach caused by anything that breaches the mucosal barrier
80
What are the most common causes of ulcers
1. Helicobacter Pylori (bacteria) 2. NSAIDS
81
What are ulcers and what can they lead to
They are an erosion of the stomach wall which if perferating can lead to peritonitis and hemorrhage
82
What is the only stomach function essential to life
Secretion of intrinsic factor
83
What is emesis
vomiting
84
What are complications caused by excessive vomiting
Dehydration, electrolyte and acid-base imbalances
85
What is alkalosis
When there is a ph imbalance in the body
86
What PRODUCES bile
Liver
87
What is bile
a fat emulsifier (makes fat breakdown easier)
88
What stores bile
Gallbladder
89
what are the pancreases main functions
supply most enzymes needed to digest chyme and store bicarbonate to neutralize stomach acid
90
**What organ are the liver gallbladder and pancreas associated with **
The small intestine
91
What is the largest gland in the body
Liver
92
What are the lobes of the liver
right, left, caudate, and quadrate
93
*which duct leaves the liver*
*common hepatic duct*
94
*Which duct connects to the gallbladder*
*Cystic duct*
95
*which duct is a union of the common hepatic and cystic duct*
*common bile duct*
96
What is a hepatocyte
The functional unit of liver cells
97
What does the liver do and an example
Produces bile and processes bloodborne nutrients
storing glucose as glycogen
98
What are the fat soluble vitamins and where are they stored
DEAK
they are stored in the liver
99
what organ detoxifies
The liver (detox alcohol or ammonia for example)
100
describe bile
Yellow-green alkaline (basic) solution
101
What are bile salts and what do they do
They are cholesterol derivatives that function in fat emulsification and absorption
102
What is bilirubin
pigment formed from dead heme cells
103
What is the final product of bilirubin and the process
Bacteria in the intestine turns Bilirubin into stercobilin giving feces brown color
104
What usually causes hepatitis
Viral infection
hepatitis B and C very worrisome
can also be caused by drug toxicity and mushroom poisoning
105
what is cirrhosis and what causes it
rock like formations on the liver usually from excessive alcohol use or chronic hepatitis
106
what is portal hypertension caused by
Cirrhosis causes hepatic portal to become fatty restricting blood flow
107
What is important to note when thinking about a liver transplant
The liver can fully regenerate from an 80% removal(in 6-12 months), thus if you can salvage 20% of a patients liver a transplant would not be necessary.
108
What stores and concentrates bile
the gallbladder
109
Where does the gallbladder release stored bile into
The cystic duct which flows into the common bile duct
110
What organ is bile released into
The duodenum of the small intestine
111
What causes gallstones
too much cholesterol or too few bile salts
112
What are some consequences of gallstones
pain during gall contraction due to crystals, blockage of flow of bile from gallbladder, obstructive jaundice
113
What is obstructive jaundice
Blockage causes bile salts and pigments to build up in blood resulting in yellow skin
114
What complication is associated with these treatments Crystal dissolving drugs, ultrasound vibrations(lithotripsy), cholecystectomy
Gallstones
115
where is the pancreas
Mostly retropertineal, deep to the greater curve
116
What is the most important function of the pancreas and what is its other function
the most important is exocrine function which secretes enzymes and secretin and its other function is endocrine releasing insulin and glucagon
117
What composes the pancreatic juice
watery ph8 sodium carbonate rich solution to neutralize chyme containing any acid and digestive enzymes
118
What are the digestive enzymes produced by the pancreas
lipases(fat)
proteases(protein)
amylases(carbs)
nucleases(nucleic acids)
119
What is special about proteases secreted by the pancreas
It is an inactivated form that acts as a switch to other enzymes
119
What is the process of protease after release in duodenum
Enteropeptidase converts trypsinogen to trypsin
trypsin activates more trypsinogen
activates procarboxypeptidase into carboxypeptidase
activates chymotrypsinogen into chymotrypsin
120
***what controls the ENTRY of bile and pancreatic juice into the duodenum***
***the hepatopancreatic sphincter***
121
Why is Bicarbonate in the pancreatic juice important
Because it acts as a buffer protecting the intestine from stomach acid
122
what regulates pancreatic and hepatic secretions
hormonal and neural controls
123
what are the hormones that regulate pancreatic and bile secretions
Cholecystokinin
secretin
124
What hormone lowers production of stomach acid and increases bicarb production in pancreas
Secretin
125
What hormone increases bile secretion from the gallbladder and liver
Cholecystokinin
126
In respect to hormones and their resulting reactions what happens after you eat a meal
Cholecystokinin increases causing an increase in bile secretion to help break down fats
127
What should you think when you hear small intestine
Segmentation digestion and *absorption*
128
what are the 3 subdivisions of the small intestine
duodenum, jejunum, ileum
129
Where in the small intestine is almost all the digestion and absorption done
the duodenum and jejunum
130
What marks the end of the small intestine and the start of the large intestine
the ileocecal valve
131
what artery brings blood to the small intestine
superior mesenteric artery
132
Where do the veins of the small intestine drain into
smaller veins drain into the hepatic portal vein then into the liver
133
what does the thoracic splanchnic nerve do and what vertebra
connects the small intestines to the sympathetic nervous system
t1-t8
134
what nerve innervates the SI to the parasympathetic
vagus nerve
135
What structural modifications in the SI 600x its surface area
villi, microvilli, circular folds
136
what forces chyme to move slowly in the SI acting as a gutter
circular folds
137
What finger like projection helps move and absorb nutrients in the SI
Villi
138
What is the function of microvilli
They have brush border enzymes which are the final step of protein and carb digestion
139
What is the microvilli and where is it found
It is an extension on the mucosal cells of villi
140
What is the brush border
the fuzzy appearance microvilli gives
141
How does chemo affect the digestive tract and why
because chem targets all rapidly dividing cells it attacks the rapidly dividing epithelium of the GI tract which can cause naseau, vomiting, and diarrhea
142
What does chyme contain when it gets to the small intestine in respect to nutrients
undigested fat, partially digested proteins and carbs
143
how long does it take the small intestine to absorb all the nutrients and most water
3-6 hours
144
What organs do bile, bicarbonate, and digestive enzymes come from
liver and pancreas
145
Where do brush order enzymes come from
microvili
146
What three features are unique to the large intestine
Haustra, teniae coli, epiploic appendages
147
what are teniae coli
bands of longitudinal smooth muscle
148
what are haustra
small pocket-like sacs
149
What are epiploic appendages
fat-filled pouches of visceral peritoneum
150
What is the flow through the large intestine in order
cecum->appendix->ascending colon->transverse colon->descending colon ->sigmoid colon->rectum->anus
151
what is the appendix
mass of lymphoid tissue that stores bacteria for recolonization of gut
152
Where is the ascending colon and where does it stop
right side of the abdomen, stops at the height of the kidney
153
Where does the ascending colon end
The right colic(hepatic) flexure
154
where is the transverse colon
across the abdomen flowing right to left
155
Where is the left colic (splenic) flexure
the right turn where the transverse colon ends and the descending colon begins
156
which section of the colon goes down the left side of the abdomen
the descending colon
157
What is the s shaped colon division that travels through the pelvis
the sigmoid colon
158
What does the rectum do
stops feces being passed with gas
159
What are the two sphincters of the anus
the internal and external
160
Which anal sphincter is controlled voluntarily
external sphincter
161
Which anal sphincter is controlled involuntarily
the internal sphincter
162
what is Appendicitis and when is it most common
acute inflammation of the appendix
in adolescence
163
what are complications associated with appendicitis
venous drainage impairment causing ischemia and necrosis, peritonitis
164
pain in umbilical region, moving to lower right quadrant, naseau, vomiting, fever loss of appetite are symptoms of what
Appendicitis
165
What are the treatments for appendicitis
removal of appendix
166
what can happen when too many antibiotics are taken
Probiotics get wiped out in the GI allowing bacteria like clostridium difficile to flourish in the intestine
167
What is C.Diff the most common example of
Antibiotic-associated diarrhea
168
What can C.Diff lead to
sepsis and bowel perforation due to colitis
169
how long does residue remain in the large intestine
12-24 hours
170
Which organ does NOT breakdown food
Stomach, Small intestine, Large intestine, mouth
Large intestine
171
What organ reabsorbs water, electrolytes, and vitamins
Large intestine
172
Which organs main functions are reabsorbing water and defecation
Large intestine
173
Which organ is not essential for living
pancreas, liver, small intestine, large intestine
large intestine
174
What is an ileostomy
A surgery where the terminal ileum is brought outside the abdomen releasing feces into a bag
175
what and where are haustral contractions and when do they happen
they are the majority of contractions in the colon, contract in response to distension
176
what reflex is activated by presence of food in stomach and what does it cause
Gastrocolic reflex
it causes movement of mass in large intestine
177
what do the descending colon and sigmoid colon mainly do
act as storage resevoir
178
What are abdominal pain, farting, stool changes, bloating, naseau and depression symptoms of
IBS
179
What can make IBS worse
Stress
180
what initiates the spinal defication reflex
distension
181
What happens when the defecation reflex is initiated
Parasympathetic pathway relaxes internal anal sphincter, and stimulates contraction of the rectum and sigmoid colon
182
What is a possible affect of a spinal injury on bowel movement
This could sever the spinal defecation reflex causing person to be unaware of their need to have a bowel movement
183
When and why does diarrhea occur
When the large intestine doesn't have time to absorb water
184
What is the most common cause of diarrhea
irritation of colon by bacteria
185
What can happen if diarrhea is prolonged
dehydration and electrolyte imbalance (acidosis and loss of potassium)
186
Why is prolonged diarrhea worrisome in kids
They become dehydrated much faster than adults
187
What happens when food remains in colon for too long
constipation
188
What are some causes of constipation
insufficient fiber or fluid in diet, lack of exercise, laxative abuse, improper bowel habits
189
what are the only molecules small enough to be absorbed by the body
monomers
190
What type of reaction do enzymes do and what does it mean
Hydrolysis which is adding water to break chemical bonds
191
Where are the only places where amylases are present
mouth and intestines
192
Where are lactase, maltase, and sucrase found
in the brush border of the jejunum and ileum
193
when is protein first digested
When it gets to the stomach
194
What are sources of protein other than in diet
broken down mucosal cells and and digestive enzyme
195
What is the order of protein break down
large polypeptide-> small polypeptide and small peptides-> amino acid monomers
196
what is a common example of malabsorption
celiacs disease
197
Which portion of the spine does the spinal defecation reflex travel
t12-l5 s1-2
198
