Lecture Test #3 Flashcards
1
Q
What are the functions of the digestive system?
(ASDIME)
A
-ingestion
-motility
-secretion
-digestion
-absorption
-elimination
2
Q
What is ingestion?
A
Taking food into mouth
3
Q
What is secretion?
A
Release of water, acid, buffers, and enzymes into lumen of GI tract
4
Q
What is Mixing and propulsion? (Motility)
A
Churning and movement of food through GI tract
5
Q
What is absorption?
A
Passage of digested products from GI tract into blood and lymph
6
Q
What is digestion?
A
Mechanical and chemical breakdown of food
7
Q
What is defecation? (Elimination)
A
Elimination of feces from GI tract
8
Q
What do accessory organs do?
A
Assist with digestion
9
Q
What are the main organs of digestion?
A
-mouth
-pharynx
-esophagus
-stomach
-small intestine
-large intestine
-rectum
-anal canal
10
Q
What are the accessory organs of digestion?
A
-salivary glands
-tongue
-teeth
-liver
-gallbladder
-pancreas
11
Q
Where is bile produced?
A
Liver
12
Q
Where is bile stored?
A
Gallbladder
13
Q
What are the salivary glands? (In order from superior to inferior)
A
-parotid glands (superior)
-sublingual glands
-submandibular glands (inferior)
14
Q
How many deciduous (baby) teeth do humans have?
A
20
15
Q
How many permanent (adult) teeth do humans have?
A
32
16
Q
Where is the pharynx located?
A
Posterior walls of oropharynx and laryngopharynx
17
Q
What does the pharynx do?
A
Contains muscles that contribute to swallowing
18
Q
What does the esophagus do?
A
Transports food from pharynx to stomach
19
Q
What is GERD?
A
gastroesophageal reflux disease
(Acid reflux)
20
Q
What is peristalsis?
A
Ability to move food
21
Q
What is segmentation?
A
Mixing and churning of food with digestive juices
22
Q
What are the walls of the GI tract in order?
A
-serosa (outer)
-muscularis
-submucosa
-mucosa (inner)
23
Q
What are the divisions of the stomach?
A
-fundus
-body
-pylorus
24
Q
What are the sphincter muscles?
A
-cardiac sphincter
-pyloric sphincter
25
What do parietal cells produce?
HCI
26
What does HCI do?
-kills bacteria
-denatures proteins
-helps convert pepsinogen into pepsin
27
What type of cells are gastric glands composed of?
-chief cells
-endocrine cells
-parietal cells
28
What are the functions of the stomach?
-reservoir for food
-chemical and mechanical digestion
-secretes intrinsic factor
-produces gastrin
-protection
29
What is mechanical digestion?
Physical breakdown of food into smaller particles (teeth and tongue)
30
What is chemical digestion?
Reactions that break macromolecules into their subunits
(Enzymes from saliva, stomach, pancreas)
31
What are the hormones of motility?
-gastrin
-secretin
-cholecystokinin (CCK)
32
Where does the small intestine receive chyme from?
Stomach
33
Where do secretions from the liver and pancreas enter the GI tract?
Near junction of stomach and small intestine
34
What is important to the digestive process of the small intestine?
Secretions
35
What are the functions of the Liver?
-detoxification
-bile synthesis and secretion
-metabolism
-storage
-production of plasma proteins
-produces urea
-helps regulate blood cholesterol level
36
What are the bile ducts?
-right and left hepatic ducts
-cystic duct
-common bile duct
37
What is bile composed of?
-water
-bilirubin
-bile salts
-cholesterol
-bicarbonate
-electrolytes
38
Where does the gallbladder eject bile to?
Duodenum
39
What type of cells is insulin?
Beta cells
40
What type of cells is glucagon?
Alpha cells
41
Pancreatic duct
Joins the bile duct at the hepatopancreatic ampulla
42
Accessory pancreatic duct
Allows pancreatic juice to be released into the duodenum
43
Pancreatic juice
Alkaline (basic) mixture of water, enzymes, zymogens, sodium bicarbonate, electrolytes
44
What antagonizes glucagon?
Insulin
45
What does insulin stimulate?
-glucose and amino uptake by muscle
-glycogen, fat, and protein synthesis
46
What can absorb glucose without insulin?
-brain
-liver
-kidneys
-RBC’s
47
What does glucagon stimulate?
Glycogenolysis and fat catabolism
48
What does glucagon promote?
Absorption of amino acids by the liver for gluconeogenesis
49
What is gastrin released by?
The stomach
50
What does gastrin cause?
Release of HCI and pepsinogen
51
What is secretin released by?
Duodenum
52
What is the release of secretin stimulated by?
Acidic chyme
53
What does secretin do?
Stimulates the pancreas to release bicarbonate-rich fluid
54
What does secretin potentiate?
Cholecystokinin (CCK)
55
What is cholecystokinin (CCK) released by?
Duodenum
56
What does CCK stimulate?
-bile secretion
-pancreatic secretion of enzymes
57
What does CCK do?
Inhibits gastric motility and secretion
58
What are the small intestines in order?
1. Duodenum
2. Jejunum
3. Ileum
59
How long is the duodenum?
About 10 inches
60
How long is the jejunum?
About 3-6 ft long
61
Where does most digestion and nutrient absorption occur?
Jejunum
62
How long is the ileum?
About 6-9 ft long
63
What is the purpose of segmentation?
Mix and churn, not to move material along
64
Where does carbohydrate digestion begin?
The mouth
65
Where does carbohydrate digestion end?
Small intestine
66
Where does protein digestion end?
Small intestine
67
Where does protein digestion begin?
Stomach
68
Where does fat digestion begin?
Small intestine
69
Where does fat digestion end?
Small intestine
70
What requires bile to be digested?
Fat
71
What are some primary nutrients absorbed by the stomach?
-alcohol (20%)
-water (minor amount)
72
What are some primary nutrients absorbed by the small intestine?
-calcium
-magnesium
-iron
-glucose
-amino acids
-fats
-vitamins
-water (70-90%)
-alcohol (80%)
73
What are some primary nutrients absorbed by the large intestine?
-sodium
-potassium
-fatty acids
-gases
-water (10-30%)
74
How much of the total amount of alcohol and water is absorbed by the stomach?
Alcohol - 20%
Water- minor amount
75
How much of the total amount of alcohol and water is absorbed by the small intestine?
Alcohol- 80%
Water- 70-90%
76
How much of the total amount of water is absorbed by the large intestine?
10-30%
77
What does the large intestine consist of?
-cecum
-colon
-rectum
78
What are the four different colons?
-ascending colon
-transverse colon
-descending colon
-sigmoid colon
79
Where is the appendix attached to?
Lower end of cecum
80
What does the bacteria that populates the large intestine do?
-helps synthesize vitamins B and K
-ferments cellulose and other undigested carbs
81
What does feces consist of?
75% water and 25% solids
82
What do the solids of feces consist of?
-30% bacteria
-30% undigested fiber
-10-20% fat
-small amount of mucous
-epithelial cells
83
What is defecation?
Bowl movement. Release of waste
84
What is constipation?
Difficult bowel movement (less than 3 a week)
85
What is diarrhea and what can it lead to?
Loose, watery stools. Can lead to dehydration
86
87
What are polysaccharides?
Complex carbohydrates, starch, fiber
88
What are 3 carbohydrates?
-polysaccharides
-disaccharides
-monosaccharides
89
What are 3 types of monosaccharides?
-glucose
-galactose
-fructose
90
Glucose
Primary source of energy
91
Galactose
Converted by liver to glucose
92
Fructose
Used by sperm, converted by liver to glucose
93
Glycogenesis
Formation of glycogen in liver and muscle
94
Glycogen in liver
Maintains blood glucose levels
95
Glycogen in muscle
Used by the muscle for energy
96
Glycogenolysis
-Glycogen is broken down to glucose
-increases blood glucose levels
97
Gluconeogenesis
Production of glucose from alternate sources
98
Lipogenesis
Production of fat from carbohydrates, proteins and fats
99
What is required in the diet?
Essential fatty acids
100
What are 3 types of lipids?
-triglycerides
-phospholipids
-cholesterol
101
What produces more energy: Lipid catabolism or carbohydrates
Lipid catabolism
102
LDL (low density lipoprotein)
-carries lipids from liver to cells
- “bad cholesterol”
103
HDL (high density lipoprotein)
- carries cholesterol from cells to liver for disposal
- “good cholesterol”
104
Protein anabolism
-most important
-structural, hormones, enzymes, transport molecules
- 8-9 essential amino acids
105
Protein catabolism
-energy
-protein balance
-nitrogen balance
106
What is protein balance?
Amount of protein ingested vs amount used
107
What is nitrogen balance?
Amount of nitrogen ingested vs amount excreted
108
Positive nitrogen balance =
Growth
109
Negative nitrogen balance =
Wasting
110
What is essential and must be obtained from diet?
Vitamins and minerals
111
Fat soluble
-dissolves in fat
-**stored in the body**
-requires bile for absorption
-possibly toxic
112
Water soluble
-dissolves in water
-**not stored in body**
-seldom toxic
113
What do vitamins serve as?
Coenzymes
114
What do minerals serve as?
Cofactor
115
What are minerals?
Inorganic elements or salts found in the earth
116
What are some examples of minerals?
-iron
-iodine
-potassium
-sodium
-calcium
117
Basal metabolic rate
-energy required for activities
-controlled by thyroid hormone
-higher in men than women
-decreases with age
118
Total metabolic rate
Combination of:
-basal metabolic rate
-energy for voluntary activities
-energy to digest food
119
Energy in = energy out
-energy balance
-constant weight
120
Energy in is greater than energy out=
-excess energy
-weight gain
121
Energy in is less than energy out=
-energy deficit
-weight loss
