Domain I: Principles of Dietetics: Principles of human anatomy, physiology, microbiology, and biochemistry Flashcards
(188 cards)
1
Q
Food in the oral cavity is chewed and mixed with ____ secreted by the parotid, submaxillary, and sublingual glands in the mouth
A
Saliva
2
Q
Food then passes into the stomach via the esophagus through the cardiac valve into the ____, which is the upper portion of the stomach that holds the bulk of the food to be digested
A
Fundus
3
Q
Most digestion in the stomach occurs in the ____ (lower) region
A
Pyloric
4
Q
From the pyloric region, food is then forced into the ___ ____ through the pyloric valve of the stomach
A
Small intestine
5
Q
Complete digestion occurs in the three parts of the small intestine, which are:
A
-Duodenum
-Jejunum
-Ileum
6
Q
The hepatic duct from the ____ joins with the cystic duct from the ____
A
Liver; Gallbladder
7
Q
____ is produced in the liver and stored in the gallbladder
A
Bile
8
Q
Roles of the liver:
A
-Produces bile
-Produces glucose
-Stores glycogen
9
Q
The ____ lies between the duodenum and the stomach
A
Pancreas
10
Q
Undigested food and water pass through the ____ ____ into the large intestine/colon
A
Ileocecal valve
11
Q
Chemical or enzymatic digestion occurs mainly in the ___ ___, but some in the stomach
A
Small intestine
12
Q
In the stomach begins the process of proteolysis by protease ____ and _____
A
Pepcin and HCL
13
Q
Limited continuation of starch hydrolysis occurs in the stomach due to the action of salivary ____
A
Amylase
14
Q
In the stomach, the hormone _____ is released and stimulates gastric secretions and motility
A
Gastrin
15
Q
The hormone cholecystokinin is released from the ____ when fat enters
A
Duodenum
16
Q
Cholecystokinin contracts the gallbladder to release ____, and stimulates the pancreas
A
Bile
17
Q
The hormone secretin is released from the ____
A
Duodenum
18
Q
Secretin stimulates the flow of ____ ____ (bicarbonate) and water in the duodenum
A
Pancreatic juice
19
Q
Secretin inhibits ____ ___ secretion
A
Gastric acid
20
Q
Glucagon-like peptide (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), are released from the intestine in the presence of ____ and ____
A
Glucose and fat
21
Q
Glucagon-like peptide (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) stimulate ____ synthesis and release
A
Insulin
22
Q
_____ is the process of chewing that produces a bolus
A
Mastication
23
Q
Rhythmic contractions of the esophagus force food into the stomach where it is mixed with gastric juice and reduced to ____, which is acidic
A
Chyme
24
Q
Gastric emptying of a meal usually takes between ___ and ___ hours
A
2 and 6
25
Carbohydrate and protein-rich foods empty from the stomach at about the same rate, but high ____ foods and complex carbohydrates, especially ____ fibers, slow gastric emptying
Fat; soluble
26
Acidic chyme enters the _____, mixes with fluid and bicarbonate ions from the pancreas in order to neutralize the acid
Duodenum
27
Most digestion is completed by the middle of the ____ (nutrients absorbed include amino acids, fatty acids, glycerol, simple sugars, minerals, and vitamins)
Jejunum
28
_____ is the rhythmic movement of the small intestine
Peristalsis
29
_____ digestion occurs in the colon
Bacterial
30
The large intestine absorbs ____ and ____, as well as vitamins
Water and salts
31
The large intestine absorbs vitamins synthesized by bacteria, which are used by GI mucosal cells; these vitamins include:
-Vitamin K
-B12 (cobalamin)
-Thiamin (B1)
-Riboflavin (B2)
32
Colonic ____ is the process of anaerobic fermentation and absorption of end-products of carbohydrates, fiber, and amino acid breakdown
Salvage
33
Bacterial digestion converts malabsorbed carbohydrates and fiber into...
-Short-chain fatty acids
-Gases (H2, CO2, N, CH4)
34
Short-chain fatty acids like acetate, butyrate, propionate, and lactate stimulate ____ and ____ absorption in the colon and provide substrates for energy production
Water and sodium
35
The mouth can digest carbohydrates with the enzyme ____; fat and protein are also partially mechanically digested
Amylase
36
Amylase breaks starch into ____ and then ____
Dextrin; maltose
37
The stomach continues digestion of ___ and ___ through the action of amylase and mechanical digestion
Carbohydrates and fat
38
The stomach also continues with the digestion of protein through _____, which involves chemicals and enzymes
Proteolysis
39
____ is an enzyme that is created with the combination of pepsinogen and hydrochloric acid of the stomach
Pepsin
40
Pepsin acts on proteins to form ____ and ____
Proteose and peptones
41
Carbohydrates are digested in the small intestine with the help of pancreatic ____
Amylase
42
Intestinal ____ breaks down sucrose into glucose and fructose
Sucrase
43
Intestinal _____ breaks maltose down into glucose and glucose
Maltase
44
Intestinal ____ breaks lactose down into glucose and galactose
Lactase
45
What is the order of enzymes that are available for carbohydrate digestion?
1. Maltase, sucrase
2. Lactase
3. Pancreatic amylase
46
Fat is digested in the small intestine through the action of...
-Bile salts (gallbladder)
-Lipase (pancreas)
-Cholesterol esterase (pancreas)
-Phospholipase (pancreas)
47
Bile salts from the gallbladder ____ fat
Emulsify
48
Lipase breaks down ____ into free fatty acids and glycerol
Triglycerides
49
Cholesterol esterase breaks down cholesterol into ____ ____
Cholesterol esters
50
Phospholipase breaks down phospholipids into ___ and ___ ___ ___
Lysolecithin; free fatty acids
51
Protein is broken down in the small intestine through the action of...
-Trypsin (pancreas)
-Chymotrypsin (pancreas)
-Carboxypeptidase (pancreas)
-Aminopeptidase (intestine)
-Dipeptidase (intestine)
52
Trypsin from the pancreas breaks protein, proteose, and peptones into ____
Polypeptides
53
Chymotrypsin from the pancreas breaks proteose, and peptone into ____ and ____
Polypeptides and dipeptides
54
The carboxypeptidase from the pancreas breaks down polypeptides into ____ and ____ ____
Dipeptides and amino acids
55
Aminopeptidase from the intestine breaks down polypeptides into ____ and ___ ___
Peptides and amino acids
56
Dipeptidase from the intestine breaks down dipeptides into ____ ____
Amino acids
57
Carbohydrates are absorbed in the small intestine and then metabolized in the liver by being converted to ____ or ____
Glucose or glycogen
58
Sources of glucose in the body:
-Dietary
-Liver glycogen
-Products of intermediary carbohydrate metabolism (conversion of lactic acid and pyruvic acid)
59
_____ amino acids are carbohydrate sources that also contain 68% amino acid
Glucogenic
60
Glucogenic amino acids yield glucose following _____
Deamination
61
_____ is the most glucogenic amino acid; it is catabolized to pyruvate or to Kreb's cycle intermediates
Alanine
62
_____ is a carbohydrate source that contains 10% fat; it can be converted to glucose
Glycerol
63
Fatty acids and muscle glycogen do not contribute to the body's supply of ____
Glucose
64
Uses of glucose:
-Energy
-Storage (glycogenesis in muscle and liver, lipogenesis)
-Small amount of converted into other carbohydrate compounds (ribose needed for form RNA, DNA)
65
Insulin is released by ____ cells of the pancreas
Beta
66
Roles of insulin:
-Increases cell permeability to glucose
-Fosters glycogenesis and lipogenesis
67
Glucagon is produced by ____ cells of the pancreas
Alpha
68
Glucagon induces _____, which converts glycogen to glucose
Glycogenolysis
69
Glucocorticoids break protein into glucose through the process of _____
Gluconeogenesis
70
Epinephrine is produced in the ____ ____
Adrenal medulla
71
Roles of epinephrine:
-Stimulates sympathetic nervous system
-Stimulates liver and muscle glycogenolysis (glycogen->glucose)
-Decreases release of insulin from pancreas during catabolic stress
72
Growth hormone and adrenocorticotropic hormone are insulin _____
Antagonists
73
Glucose in the cell is oxidized to produce...
-Energy
-Carbon dioxide
-Water
74
Glycolysis occurs in the ____ of the cell
Cytoplasm
75
The purpose of glycolysis is to produce ____ for the Kreb's cycle by breaking down glucose, with or without oxygen, into pyruvate or lactose (depending on oxygen or not)
Pyruvate
76
The end product of aerobic glycolysis is ____
Pyruvate
77
The end product of anaerobic glycolysis is ____
Lactate
78
Glucose enters the cell, aided by insulin; it combines with phosphorus in the presence of magnesium to form _______, which proceeds pyruvic acid
Glucose-6-phosphate
79
Glucose-6-phosphate may lead to synthesis of ____
Glycogen
80
Liver glycogen releases ____ to blood to maintain normal blood sugar; this process requires glucose-6-phosphate
Glucose
81
____ cells do not have glucose-6-phosphate, so glycogen in those cells is only used for those cells
Muscle
82
Glucose-6-phosphate also proceeds through the ____ shunt (side-channeling of glucose)
Pentose
83
The pentose shunt does not require ____
ATP
84
The pentose shunt produces ____, which is part of RNA
Ribose
85
The pentose shunt also produces ____, which is essential for the synthesis of fatty acids because it contains niacin
NADPH
86
Pyruvic acid can proceed to form ___ ____, which is used for muscle contractions when energy needs exceed the supply of oxygen (only a small amount is produced)
Lactic acid
87
In the ____ Cycle, lactate is released from tissue, transported to the liver, and converted back to glucose as pyruvate
Cori
88
Most of pyruvic acid is converted to form ____ ____ (active acetate)
Acetyl CoA
89
Pyruvate is the main substrate for energy production in the ____ cycle
Kreb's
90
What things are required for the Kreb's Cycle?
-Thiamin (TDP)
-Niacin (NAD)
-Riboflavin (FAD)
-Pantothenic acid (CoA)
-Magnesium
-Lipoic acid
91
What are two other names for the Kreb's Cycle?
-Tricarboxylic Acid Cycle (TCA cycle)
-Citric acid cycle
92
The Kreb's Cycle takes place in the ____ of the cell
Mitochondria
93
Acetyl CoA comes from...
-Pyruvic acid (CHO)
-Oxidation of fatty acids
-Degradation of the carbon skeleton of certain amino acids
94
Acetyl CoA is the intermediate breakdown product of ___, ___ and ___
Carbohydrates, protein, and fat
95
Fatty acids enter the Krebs cycle as a ___-___ fragment
2-carbon
96
The Krebs cycle produces ____% of the body's energy at ATP, in addition to CO2 and water
90
97
____ is the fuel needed to keep the Kreb's cycle going
Carbohydrate
98
____ is the main carbohydrate fuel for the Krebs cycle and is formed from pyruvic acid and some amino acids
Oxaloacetate
99
Oxaloacetate reacts with acetyl CoA to form ___ ___ which starts the cycle
Citric acid
100
If there is not enough oxaloacetate coming in from carbohydrates to maintain the krebs cycle efficiently, acetyl CoA coming in from fat cannot be handled properly and is diverted for form _____ _____
Ketone bodies
101
Alpha ketoglutaric acid (produced from amino acids through gluconeogenesis) needs _____ for decarboxylation
Thiamin
102
Full oxidation of 1 molecule of glucose yields ____ ATP
38
103
Amino acids are broken down and transported to the capillaries, the portal bloodstream, and finally the ____
Tissues
104
_____ is needed for the transport of amino acids
Pyridoxine
105
What are three branched-chain amino acids (BCAAs)?
-Valine
-Leucine
-Isoleucine
106
Exercise releases ____ from muscle protein
Alanine
107
Alanine is transported to the liver, deaminated, and converted to ____
Glucose
108
Also during exercise, the oxidation of ____ (a BCAA) increases
Leucine
109
Tyrosine can be synthesized by _____
Phenylalanine
110
Cysteine can be synthesized from ____
Methionine
111
Nitrogen balance measures body _____; compares intake to output
Equilibrium
112
A nitrogen balance of ____ indicates maintenance/equilibrium
0
113
A positive nitrogen balance indicates a net ____ in body protein (commonly seen in infants, teens, pregnancy, and healing)
Gain
114
A negative nitrogen balance indicates ____ of body protein and/or inadequate intake
Erosion
115
Formula for determining nitrogen balance:
[(protein intake (g)/6.25)] - (UUN + 4)
116
___ ____ is a way to determine the quality of protein in food; it uses the nitrogen balance technique to determine the fraction of absorbed nitrogen retained for growth and maintenance
Biological value
117
Eggs have a biological value of ____, meaning that 100% of the nitrogen absorbed is retained
100
118
___ ___ ___ is another way of determining the quality of protein in food; it measures the amount of protein actually used
Net protein utilization
119
Formula for determining net protein utilization:
(Nitrogen intake - Nitrogen output (retained)) / (Nitrogen intake)
120
Another way of determining the quality of protein in food is...
Protein Digestibility Corrected Amino Acid Score (PDCAAS)
121
PDCAAS is the protein coefficient of _____; estimates the percentage of protein in each food category that is actually digested (animal 97%, plant proteins 70-90%)
Digestibility
122
Anabolism is another word for ____
Synthesis
123
The amount of ____ in a cell indicates the number of cells per organ, thus, helps determine stages of growth
DNA
124
DNA forms RNA on ____
Ribosomes
125
RNA forms a template (mold) which carries the plan to the ______
Cytoplasm
126
What B vitamin is involved in protein catabolism?
Pyridoxine (B6)
127
The first step in protein catabolism is ____, which involves splitting NH2 by hydrolysis in the liver
Deamination
128
NH2 is converted into ____ (NH3) which is toxic
Ammonia
129
Most of the ammonia is converted into ____ and excreted in the kidneys
Urea
130
Some ammonia is converted into ____, and some is used to make the nonessential amino acids through transamination
Purines
131
The remaining carbon chain is a ____ which can be oxidized for energy
Ketoacid
132
All proteins are oxidized to produce ____ ___ and ____
Carbon dioxide, water
133
What hormones are anabolic?
-Pituitary growth hormone
-Thyroid hormone
-Insulin
-Testosterone
134
What hormones are catabolic (stimulate gluconeogenesis)?
-Adrenal steroids
-Glucocorticoids
135
The end products of fat digestion:
-Monoglycerides
-Diglycerides
-Glycerol
-Fatty acids
136
Glycerol, short-chained fatty acids, and some phospholipids are absorbed directly into portal ____
Blood
137
Glycerol is ____-soluble
Water
138
Short-chain fatty acids have under _____ carbons
12
139
Monoglycerides, diglycerides, and long-chain fatty acids combine with the help of bile salts to form ____
Micelles
140
Micelles bind to protein to form lipoproteins like _____
Chylomicrons
141
Micelles can penetrate the intestinal mucosa, travel through the lymph, and into the thoracic duct, and into the ____
Blood
142
Some cholesterol is absorbed with ___ ___, while most is absorbed with ____ ____
Bile salts, cholesterol esterase
143
Cholesterol is converted to cholesterol esters and excreted by the liver as _____
Bile
144
____ is the synthesis and/or deposition of fat; promoted by insulin
Lipogenesis
145
_____ tissue is the most active site of lipogenesis
Adipose
146
Fatty acids + glycerol makes _____
Triglycerides
147
Lipogenesis requires ____ from the pentose shunt
NADPH
148
The liver ____ fat, but should not store it
Synthesizes
149
To prevent the accumulation of fat, lipotropic factors like ____ produce lipoproteins which transfer fatty acids out of the liver
Choline
150
_____ is a diet-derived lipoprotein made up of mostly triglyceride
Chylomicron
151
VLDL is about ____ triglyceride
Half
152
LDL is smaller and made up of mostly ____
Cholesterol
153
HDL is rich in _____
Protein
154
_____ causes oxidation of fat that forms acetyl CoA which then enters the Krebs Cycle
Lipolysis
155
What increases the rate of fat mobilization (lipolysis)?
-Glucocorticoid
-Thyroxine
-Epinephrine
-ACTH
156
What decreases the rate of fat mobilization (lipolysis)?
-Insulin
-Growth hormone
-Glucagon
157
Normal fat metabolism requires adequate ____ from complete fat oxidation
Carbohydrate
158
Without carbohydrate, ___ ___ form from the breakdown of fatty acids; they are made of acetoacetic acid, acetone, and beta-hydroxybutyric acid
Ketone bodies
159
When no carbohydrates are present, acetoacetic acid and beta-hydroxybutyric acid enter the blood and are taken to the peripheral tissues, are converted back to ____ ____, and oxidized as fuel
Acetyl CoA
160
Inadequate carbohydrate intake, due to ___ or ___ ____, results in incomplete fat oxidation and buildup of ketones
Starvation; uncontrolled diabetes
161
Ketones serve as fuel for the ____ and ____, but disturb acid/base balance
Muscles and brain
162
Most nutrients are absorbed through ____ transport (glucose, amino acids, Na, K, Mg, Ca, Fe)
Active
163
One example of active transport is the ____ pump, which works through uphill pumping from a lower to higher concentration gradient (it requires energy from ATP)
Sodium
164
Simple diffusion is used for the absorption of some ____ and ____; moves from higher to lower concentration such as the intestine to the blood to the lymph
Water and electrolytes
165
_____ diffusion is carrier facilitated and moves things from higher to lower concentration; used for the absorption of water-soluble nutrients
Passive
166
What things aid in the absorption of vitamin A?
-Bile salts
-Pancreatic lipase
-Fat
167
Vitamin D is hydroxylated in the ____, and then in the ____
Liver; kidney
168
Vitamin D requires ____ ____ and the acidity of chyme to be absorbed
Bile salts
169
Vitamin D accompanies the absorption of ____ and ____
Calcium, phosphorus
170
_____ aids in the absorption of riboflavin
Phosphorus
171
Vitamin B12 (cyanocobalamin) is absorbed in the ileum and is aided by stomach secretions like ____ and ____ ____
HCL and intrinsic factor
172
___ _____ aids in the absorption of non-heme iron
Hydrochloric acid
173
____ decreases iron absorption because it binds oxalates
Calcium
174
Absorption of folate is ____-dependent, as it cleaves polyglutamate to monoglutamate
Zinc
175
Folic acid in fortified foods and supplements is present as ____
Monoglutamate
176
The ____ is a key brain structure involved in the control of food and energy intake
Hypothalamus
177
Low levels of serotonin increase ____ intake
Carbohydrate
178
_____ is a hormone produced by fat cells in response to food intake
Leptin
179
Leptin induces _____ and suppresses appetite
Satiety
180
Leptin enhances ____ ____
Energy expenditure
181
____ is a hormone produced in the stomach and intestine to stimulate appetite and growth hormone secretion from the pituitary
Ghrelin
182
Ghrelin ____ fat utilization in adipose
Decreases
183
Low leptin and high ghrelin promote excess ___ ___
Food intake
184
____ determinants of health are conditions in the places where people live, learn, work, and play that affect a wide range of health risks and outcomes
Social
185
Examples of social determinants of health:
-Economic stability
-Education
-Social and community context
-Access to healthy food and safe neighborhoods
-Access to health care
186
A ____ is the sum of the organism's genetic material
Genome
187
Nutritional ____ focuses on diet and lifestyle-related disorders resulting from the interactions between the genome and environmental factors such as nutrients, toxins, physical activities, sleep, and stress
Genomics
188
Nutritional genomics provides a greater understanding of how to use nutrition therapy to promote ____ and prevent ____
Health; disease
