Digestive System Flashcards
(140 cards)
1
Q
Occurs when gastric juices regurgutate into esophagus
Cause?
A
Heartburn; caffeine, smoking or eating/drinking in excess
2
Q
- Take in food
- Break down food
- Absorb digested materials
- Provide nutrients
- Eliminate waste
A
DIGESTIVE SYSTEM FUNCTIONS
3
Q
Layer of smooth epithelial tissue
A
Peritoneum
4
Q
Connective tissue of organs in
abdominal cavity
A
Mesenteries
5
Q
Mesentery connecting lesser curvature of stomach to liver and diaphragm
A
Lesser Omentum
6
Q
Mesentery connecting greater curvature of stomach to transverse colon and posterior body wall.
A
Greater Omentum
7
Q
First part of the digestive system
A
Oral Cavity
8
Q
Tissue type present in the oral cavity
A
Stratified squamous epithelia
9
Q
Produce saliva
A
Salivary glands
10
Q
Salivary Glands
- contains ____ to break down carbohydrates into ____
- ______ the mouth
- dissolves and _____ food
A
- enzymes; glucose
- cleanses
moistens
11
Q
Salivary enzyme that breaks down carbohydrates
A
Amylase
12
Q
Salivary enzymes that are active against bacteria
A
Lysozyme
13
Q
House taste buds and mucus
A
Tongue
14
Q
a normal adult has ____ teeth
A
32
15
Q
types of teeth
A
Incisors, canine, premolars, molars, wisdom teeth
16
Q
primary teeth consists of __ baby teeth
A
20
17
Q
Tooth structure
A
Each tooth has a crown, cusp, neck, and root
18
Q
The center of the tooth
A
Pulp cavity
19
Q
Hard covering that protects against
abrasions
A
Enamel
20
Q
Breakdown of enamel by acids from
bacteria
A
Cavities
21
Q
Roof of oral cavity
A
Palate
22
Q
hard palate vs soft palate
A
hard is anterior and soft is posterior
23
Q
Includes submandibular,
sublingual, and parotid glands
A
Salivary Glands
24
Q
Inflammation of the parotid gland
A
Mumps
25
Purely serous secretion
Parotid Gland
26
Mixed secretion, predominantly serous
Submandibular Gland
27
Mixed secretion, predominantly mucous
Sublingual Gland
28
pharynx is aka?
throat
29
Connects mouth to esophagus
pharynx
30
Tube that connects the pharynx to
the stomach
esophagus
31
Transports food to the stomach
esophagus
32
Joins the stomach at the cardiac opening
Esophagus Connection
33
Occurs when gastric juices regurgitate into the esophagus; caused by caffeine, smoking, or eating or drinking in excess
heartburn
34
Bolus (mass of food) formed in the mouth and pushed into the oropharynx
swallowing
35
Swallowing reflex initiated when the bolus stimulates receptors in the _oropharynx_
Pharyngeal phase
36
it refers to mass of food
bolus
37
Moves food from the pharynx to the stomach
Esophageal phase
38
Wave-like contractions that move food through the digestive tract (Myenteric plexus/Auerbach’s plexus)
Peristalsis
39
stomach is located in ____
abdomen
40
it is the Storage tank for food
stomach
41
Produces mucus, hydrochloric acid, and protein-digesting enzymes
stomach
42
stomach Contains a ______
that lubricates and protects epithelial cells on
the stomach wall from acidic pH (3)
thick mucus layer
43
capacity of stomach
can hold 2L of food
44
layer of stomach that produce churning action
thick muscular layer
45
Large folds that allow the stomach to stretch
rugae
46
Paste-like substance that forms when
food begins to be broken down
Chyme
47
Opening between the stomach and small intestine
Pyloric opening
48
Thick, ring of smooth
muscle around the pyloric opening
Pyloric sphincter
49
Stomach is stimulated to
contract by low blood glucose levels, usually
12-24 hours after a meal
hunger pangs
50
Stomach is stimulated to
______ by ________ levels, usually
12-24 hours after a meal
contract; low blood glucose
51
increases stomach secretions
Parasympathetic stimulation, gastrin,
histamine
52
- _1st phase_ of secretion regulation
- Stomach secretions are initiated by the sight, smell, taste, or thought of food
Cephalic phase
53
- _2nd phase_ of secretion regulation
- Partially digested proteins and distention of the stomach promote secretion
Gastric phase
54
- _3rd phase_ of secretion regulation
- Acidic chyme stimulates neuronal reflexes and secretion of hormones that inhibit gastric secretions by negative feedback loops
Intestinal phase
55
Cephalic Phase - The taste, smell, or thought
of food or tactile sensations of food in the
mouth stimulate the ______
medulla oblongata
56
Carry parasympathetic action
potentials to the stomach, where
enteric plexus neurons are activated.
Vagus Nerves
57
Stimulate secretion by parietal and chief cells and stimulate gastrin and histamine secretion by endocrine cells.
Postganglionic Neurons
58
Carried through the circulation back to the stomach, where, along with histamine, it stimulates secretion.
Gastrin
59
Distention of the stomach stimulates mechanoreceptors (stretch receptors) and activates a parasympathetic reflex. Action potentials generated by the mechanoreceptors are carried by the vagus nerves to the medulla oblongata. What phase is this?
Gastric Phase
60
Increases action potentials in vagal and chief cells that
stimulate secretion by parietal cells and stimulate gastrin and histamine secretion by endocrine cells
Medulla Oblongata
61
Distention of the stomach also activates local reflexes that increase stomach secretions
Local Reflexes
62
Carried through the circulation back to the stomach, where, along with histamine, it stimulates secretion.
Gastrin
63
In the duodenum with a pH less than 2 or containing fat digestion products (lipids) inhibits gastric secretions by three mechanisms (2-4).
Chyme
64
In the duodenum are stimulated by H+ (low pH) or lipids. Action potentials generated by the ______ are carried by the vagus nerves to the medulla oblongata (green arrow), where they inhibit parasympathetic action potentials, thereby decreasing gastric secretions.
chemoreceptors
65
Activated by H+ or lipids also
inhibit gastric secretion. what reflex is this?
local reflexes
66
Produced by the duodenum (brown arrows) decrease gastric secretions in the stomach.
Secretin and Cholecystokinin
67
Secretin and Cholecystokinin - Produced by
the ______ and ______
gastric secretions in the stomach.
duodenum; decrease
68
Weak contractions that thoroughly mix food to form chyme.
Mixing waves
69
Mixing Waves - _____ contractions that thoroughly mix food to form _____
weak; chyme
70
Stronger contractions that force chyme toward and through the pyloric sphincter.
Peristaltic Waves
71
Peristaltic Waves - _____ contractions that force chyme toward and through the pyloric sphincter.
stronger
72
**Hormonal and Neural Mechanisms** -
Stimulate _________
stomach secretions.
73
stomach empties every ___ hours after a regular meal, and ___ hours after a high-fat meal.
4 ; 6-8
74
Initiated in the body of the stomach and progresses toward the pyloric sphincter. what wave is this?
mixing wave
75
More fluid part of the chyme is pushed toward the pyloric sphincter, while the more solid contents are squeezed back toward the body of the stomach through peristaltic constriction. what movement is this?
Chyme Movement
76
Move in the same direction and in an orderly way as mixing waves but are stronger
Peristaltic Waves
77
more fluid part of the chyme is pushed toward the pyloric region, while the more solid center of the chyme squeezes past the peristaltic constriction back toward the body of the stomach. what movement is this
Chyme Movement
78
Force a few milliliters of the most fluid chyme through the pyloric opening into the duodenum. Most of the chyme, including the more solid portion, is forced back toward the body of the stomach for further mixing. what contraction is this?
Peristaltic Contractions-
79
Mucin in an alkaline fluid
Surface mucous cells
80
Mucin in an acidic fluid
Mucous neck cells
81
Chief cells
Pepsinogen & lipase
82
A 6-meter-long major absorptive organ where chyme takes 3-5 hours to pass through, containing enzymes to further break down food and secretions to protect against chyme's acidity.
Small Intestine
83
Parts of Small Intestine:
duodenum, jejunum, Ileum
84
25 cm long section containing absorptive cells, goblet cells, granular cells, endocrine cells, microvilli, and many folds. It also houses the bile and pancreatic ducts.
Duodenum
85
2.5-meter-long section responsible for nutrient absorption.
Jejunum
86
A 3.5-meter-long section of the small intestine.
Ileum
87
Its function is to absorb water from indigestible food and contains the cecum, colon, rectum, and anal canal.
large intestine
88
Joins the small intestine at the ileocecal junction and has the appendix attached.
cecum
89
9 cm structure that is often removed.
appendix
90
1.5-meter-long section with ascending, transverse, descending, and sigmoid regions.
colon
91
Straight tube that begins at the sigmoid and ends at the anal canal.
rectum
92
Last 2-3 cm of the digestive tract
anal canal
93
Food Passage – Takes ___ hours to pass
through the large intestine.
18-24
94
Feces Product is made up of?
water, indigestible food, and microbes.
95
Microbes in the large
intestine synthesize _____
vitamin K
96
Weighs about 3 lbs and is located in the ___ ____ quadrant of the abdomen under the _____. It has right, left, caudate, and quadrate lobes.
right upper; diaphragm
97
Gateway where blood vessels, ducts, and nerves enter and exit the liver
porta
98
liver Receives blood from the _____
hepatic artery.
99
what duct Transports bile out of liver
hepatic duct
100
Formed from left and right hepatic duct
common hepatic duct
101
Joins common hepatic duct and it is from gallbladder
cystic duct
102
Formed from common hepatic duct and cystic duct
common bile duct
103
(no answers!!)
**Flow of Bile and Pancreatic Secretions through Duct System of Liver, Gallbladder, and Pancreas**
1. Hepatic ducts – From liver lobes combine to form the common hepatic duct.
2. Common hepatic duct - Combines with the cystic duct from the gallbladder to form the common bile duct.
3. Common bile duct - Joins the pancreatic duct
4. Combined duct - Empties into the duodenum at the duodenal papilla
5. Pancreatic Secretions - Pancreatic secretions also enter the duodenum through pancreatic duct, which empties into duodenum.
104
Small sac located on the inferior surface of the liver that stores and concentrates bile.
gallbladder
105
Responsible for digestive and excretory functions, storing and processing nutrients, detoxifying harmful chemicals, and synthesizing new molecules. It secretes 700ml of bile each day.
liver
106
Dilutes and neutralizes stomach acid and breaks down fats.
bile
107
this stimulation Causes the gallbladder to contract, releasing bile into the duodenum
vagus and nerve stimulation
108
Produced by the duodenum and carried through the circulation to the liver, stimulates bile secretion by the liver.
secretin
109
Produced by the duodenum and carried through the circulation to the gallbladder, stimulates the gallbladder to contract, releasing bile into the duodenum.
Cholecystokinin
110
Stimulate bile secretion; over 90% are reabsorbed in the ileum and returned to the liver, where they stimulate additional secretion of bile salts.
bile salts
111
Located posterior to the stomach in the inferior part of the left upper quadrant, with its head near the midline of the body and its tail extending to the left, touching the spleen.
pancreas
112
this tissues contain pancreatic islets that produce insulin and glucagon
Endocrine Tissues
113
this tissues Produce digestive enzymes
exocrine tissues
114
Causes the pancreas to release a
secretion rich in digestive enzymes.
Parasympathetic stimulation from the vagus
nerve
115
Released from the duodenum, stimulates the pancreas to release a watery secretion, rich in bicarbonate ions.
secretin
116
Released from the duodenum, causes the pancreas to release a secretion rich in digestive enzymes.
Cholecystokinin
117
Breakdown of food occurs in ____ and ____
stomach; mouth
118
Moves food through digestive tract includes swallowing and peristalsis.
propulsion
119
Elimination of waste in the form of feces
defecation
120
______ split into disaccharides by
salivary and pancreatic amylases.
Polysaccharides
121
are Broken down into monosaccharides by disaccharidases on surface of intestinal epithelium.
disaccharides
122
Absorbed by cotransport with Na+
into intestinal epithelium
glucose
123
____ is carried by hepatic portal vein to
liver and enters most cells by facilitated
______
glucose; diffusion
124
(no answer)
**Monosaccharide (glucose) Transport**
1. Glucose is absorbed by symport with Na⁺ into
intestinal epithelial cells.
2. Symport is driven by a sodium gradient
established by a Na⁺-K⁺ pump.
3. Glucose moves out of the intestinal epithelial
cells by facilitated diffusion.
4. Glucose enters the capillaries of the hepatic
portal vein and is carried through the liver.
125
Bile salts _____ lipids
emulsify
126
Lipase breaks down lipids, forming ____
micelles
127
Micelles come into contact with the intestinal epithelium and diffuse into the cells, where they are packaged and released into _____.
lacteals
128
Lipids are stored in ____ and ____
adipose tissue; liver.
129
Attach to the cell membranes of
intestinal epithelial cells, allowing fatty acids
and monoglycerides to pass by simple
diffusion into the intestinal epithelial cells.
micelles
130
Within the intestinal epithelial cells - ____
acids and _____ are converted to
triglycerides; proteins coat the triglycerides to
form chylomicrons, which move out of the
intestinal epithelial cells by _____.
Fatty; monoglycerides; exocytosis
131
Enter the lacteals of the intestinal villi and are carried through the lymphatic system to the general circulation.
Chylomicrons
132
____ are split into ____ by enzymes secreted by the stomach and pancreas.
Proteins; polypeptides
133
Peptides and amino acids are absorbed into ____
intestinal epithelial cells.
134
____ are actively transported into cells with help from growth hormone (GH) and insulin.
Amino acids
135
Amino acids are used to build
new ___.
proteins
136
(no answer)
**Amino Acid Transport**
1. Acidic and most neutral amino acids -
Absorbed by symport into intestinal epithelial
cells.
2. Symport - Driven by a sodium gradient
established by a Na+—K+ pump.
3. Amino acids - Move out of intestinal epithelial
cells.
4. Amino acids - Enter the capillaries of the
intestinal villi and are carried through the
hepatic portal vein to the liver.
137
___ can move across the intestinal wall in either direction, depending on osmotic conditions.
water
138
99% of the water entering the
intestine is ____.
absorbed
139
are actively transported across the wall of the small intestine.
minerals
140
(no answers)
**Fluid Volumes in Digestive Tract**
1. Ingestion - 2 L
2. Salivary gland secretions - 1.5 L
3. Gastric secretions - 2 L
4. Pancreatic secretions - 1.2 L
5. Bile - 0.7 L
6. Small intestine secretions - 2 L
7. Absorption in the small intestine - 92%
8. Absorption in the large intestine - 6%-7%
9. Water in feces - 0.1 L
