Term
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Definition
| sum of all chemical reactions in cells and the body |
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Term
| Function of Digestive system in metabolism |
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Definition
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Term
| Function of Liver in metabolism |
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Definition
Metabolizes and stores fat
Synthesizes cholesterol
Metabolizes carbohydrates
Stores glycogen to regulate blood sugar
Metabolizes and stores fat soluble vitamins and many minerals
Makes bile
Detoxifies drugs
Involved in iron recycling
Makes several blood proteins (lipoprotein, clotting factors, albumin)
Alcohol metabolism |
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Term
| Function of Pancreas in Metabolism |
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Definition
Secretes insulin to lower blood sugar
Promotes glucose absorption by muscles and adipose
Increases glycolysis
Promotes glucose storage as glycogen
Secretes glucagon to raise blood sugar
Promotes breakdown of glycogen glucose
Slow glucose breakdown in cell
Synthesizes and secretes digestive enzymes |
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Term
| Function of Kidneys in metabolism |
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Definition
Filters blood for wastes urine
Reabsorb nutrients (salts, sugar)
Why normal urine should not have sugar
Sign of diabetes
Regulates blood pressure (fluid amount)
Convert precursor to active Vitamin D
Contributes to blood pH balance (electrolytes) |
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Term
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Definition
Make larger molecules from smaller molecules
Generate H2O (metabolic H2O) via dehydration synthesis
Require energy (Endothermic) |
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Term
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Definition
Breakdown of large molecules to produce smaller molecules
Consumes H2O via hydrolysis
Releases energy (Exothermic) |
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Term
| "Central Pathways" of energy metabolism |
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Definition
The “Central Pathways” of energy metabolism involve the breakdown of carbs
The breakdown pathways for both fats and proteins feed into the same central pathways
TCA (Kreb’s) Cycle, Electron Transport Chain
All pathways generate ATP the same way |
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Term
| Aerobic Cellular Respiration Equation |
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Definition
| Glucose + 6 O2 -> 6 CO2 + 6 H2O + Energy (ATP) |
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Term
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Definition
Breakdown of glucose
10 Enzymes
Cytoplasm
Occurs under both aerobic (with O2) and anaerobic (without O2) conditions
Glucose + 2 ADP + 2 Pi + 2 NAD+ 2 Pyruvate + 2 ATP + 2 NADH
NADH is an electron carrier
Two Stages |
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Term
| Fermentation (aerobic conditions) |
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Definition
| pyruvate is transported into the mitochondria for breakdown by the PDC, TCA (Kreb’s) Cycle and ETC |
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Term
| Fermentation (anaerobic conditions) |
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Definition
the ETC does not function and cannot regenerate NAD+ for glycolysis
One way for an organism to generate energy anaerobically is fermentation |
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Term
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Definition
erythrocytes and muscle during short term high intensity exercise
also in cytoplasm |
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Term
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Definition
| 2 Pyruvate + 2 ATP + 2 NADH -> 2 Ethanol + 2 CO2 + 2 NAD+ |
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Term
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Definition
| Purpose: To regenerate NAD+ for use by glycolysis, which is the cell’s only source of ATP (2 ATP/glucose) under anaerobic conditions |
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Term
PDC (Pyruvate Dehydrogenase Complex)
in MITOCHODRIAL MATRIX |
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Definition
| 2 Pyruvate + 2 NAD+ + 2 CoA --> 2 Acetyl-CoA + 2 CO2 + 2 NADH |
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Term
| Kreb's Cycle and its electron carrier |
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Definition
| 2 Acetyl-CoA + 6 NAD+ + 2 FAD + 2 ADP + 2 Pi --> 4 CO2 + 2 ATP + 6 NADH + 2 FADH2 + 2 CoA |
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Term
| Glycolysis Krebs Cycle Results |
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Definition
all six carbons from the original glucose have been released as CO2 (waste)
4 ATPs have been generated directly
2 from glycolysis, 2 from Kreb’s cycle
Substrate-level phosphorylation
However, most of the energy from glucose is held by electron carriers (NADH & FADH2)
Will be used to drive the ETC to produce much more ATP from oxidative phosphorylation |
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Term
| ETC location, requirements, Complexes, what does it form |
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Definition
Inner mitochondrial membrane
Four protein complexes
Requires O2 as final electron acceptor (Why aerobic)
Complexes I, III, IV pump protons from the matrix to the intermembrane space
Form a proton gradient
Complex II receives electrons from FADH2, does not pump protons |
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Term
| Oxidative Phosphorylation |
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Definition
ETC generates proton gradient
ATP Synthase enzyme is also in inner mitochondrial membrane
Allows protons to return to matrix via diffusion
Uses energy of proton flow to synthesize ATP from ADP & Pi
Each NADH pumps enough protons to generate 3 ATP
Each FADH2 pumps enough protons to generate 2 ATP |
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Term
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Definition
Allows protons to return to matrix via diffusion
Uses energy of proton flow to synthesize ATP from ADP & Pi |
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Term
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Definition
2 ATP/glucose
both from glycolysis |
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Term
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Definition
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Term
direct glycolysis atp production
2 NADH atp production in glycolysis |
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Definition
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Term
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Definition
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Term
Kreb's Cycle (Direct) ATP production
6 NADH
2FADH2 |
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Definition
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Term
| What happens in fat metabolism |
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Definition
Glycerol is converted to pyruvate
Used to drive gluconeogenesis
Fatty acids each broken down into 2 carbon molecules (Acetyl-CoA) thru Beta-Oxidation |
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Term
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Definition
Example) 18C fatty acid 9 acetyl-CoA
Acetyl-CoAs feed into Kreb’s Cycle |
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Term
| First step in Amino Acid Metabolism |
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Definition
Deamination
Removal of amino group
Excreted as urea in urine
Most AAs (~1/2) are converted to pyruvate
Used for gluconeogenesis
Some AAs are converted to Acetyl CoA
Feed into Kreb’s Cycle
Some AAs are converted to various intermediates in the Kreb’s Cycle |
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Term
| Alcohol Metabolism: location, process |
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Definition
Occurs in the liver
Ethanol is converted to acetaldehyde by alcohol dehydrogenase
Acetaldehyde in blood affects brain and causes “drunk” feeling
Acetaldehyde is converted to acetyl-CoA, which would be used in fatty acid synthesis |
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Term
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Definition
Process by which body can make new glucose from non-carbohydrate sources
Used to replace blood sugar during fasting
Especially one liver glycogen stores have been exhausted
Pathway is opposite of glycolysis pathway
2 Pyruvates glucose |
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Term
| Sources of Carbons for Gluconeogenesis |
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Definition
Amino acids that converted into pyruvate are the main source (90%) of gluconeogenic precursors
Why we might break down muscles during fast or dieting
2) Glycerol from triglyceride breakdown are converted to pyruvate
10% of gluconeogenic precursors
3) Lactate from fermentation in muscles and RBCs can be converted in the liver back to pyruvate, to be used for gluconeogenesis |
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Term
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Definition
body uses elevated blood sugar for energy needs
Excess glucose is first stored as glycogen
But body only stores a limited supply of glycogen
Remaining excess is converted to fat & stored |
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Term
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Definition
| excess fatty acids & acetyl–CoA are converted to fat & stored |
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Term
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Definition
amino acids are used to make new proteins
If excess amino acids are not needed, they are deaminated and converted to fat & stored |
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Term
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Definition
Body expends energy all time, even when we sleep
Basal metabolism (normal daily life processes) uses about 2/3 of body’s energy every day
Other 1/3 of our energy goes to muscle work (activity)
Fasting – voluntary energy deficit
Starvation - involuntary energy deficit
Metabolically both are handled in the same way |
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Term
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Definition
Liver glycogen is broken down to yield glucose
Released into blood to raise blood sugar
Brain & CNS can only use glucose
Fatty acids from stored body fat used to provide energy for most cells in body |
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Term
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Definition
Glycogen stores are exhausted after several hours
Proteins of muscles converted to glucose via gluconeogenesis
Brain can’t use fatty acids, only glucose
Uses about 400-600 Cal from glucose/day
Body fat provides energy for most cells |
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Term
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Definition
Cells condense most of the acetyl–CoA’s from fatty acid breakdown to make ketones
Ketones are usable by same brain cells
Others will only use glucose
Must get from gluconeogenesis
Ketosis happens in fasting, diabetes, high protein diets, alcoholism
Liver & kidney damage over long term |
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Term
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Definition
Burn less fat and protein
Uses as little energy as possible
Body becomes more efficient |
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Term
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Definition
Wasting of lean tissues (muscles)
Impaired disease resistance
Lower body temp
Less fat insulation, slower metabolism (less heat)
Disturbs salt & water balance
Lower mental alertness & mental performance (seen in school children) |
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Term
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Definition
rate at which body expends energy for normal daily involuntary activities
Varies from person to person
Can vary within individual depending on circumstances |
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Term
| Daily Energy Expenditure in Normal Person |
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Definition
About 2/3 Cal usage for basal metabolism (BMR)
About 1/3 Cal usage for daily activity
About 1/10 Cal usage due to thermic effect of food
Energy required to digest & process food
Insignificant |
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Term
| Daily Energy Expenditure in an active person |
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Definition
About 50% Cal for BMR
About 50% Cal for activity |
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Term
| 5 Factors that INfluence Energy Requirements |
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Definition
| Gender, Growth, Age, Physical Activity, Body Composition adn Size, |
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Term
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Definition
females have lower BMR than males
Males have more muscle (lean body mass)
Menstrual hormones can raise BMR just prior to menstruation
Thus, 2 different equations (men vs. women) |
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Term
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Definition
BMR higher in people who are growing
Pregnant women, children, adolescents = different equations |
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Term
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Definition
BMR decreases through adulthood as lean body mass decreases
Physical activity tends to decrease with age also
Average decrease in energy expenditure = 5% / decade |
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Term
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Definition
clustered based upon typical intensity of efforts
PA factor is included in equations |
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Term
| EER Body Composition and Size |
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Definition
BMR is higher in tall and thin people
More weight, more energy spent on BMR
So height & weight included in calculations |
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Term
| Determining EER: Height and Weight |
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Definition
Determine weight (wt) in kg (lbs/2.2)
Determine height (ht) in m (in/39.37) |
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Term
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Definition
| [662 – (9.53 x age)] + PA x [(15.91 x wt) + 539.6 x ht)] |
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Term
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Definition
| [354 – (6.91 x age)] + PA x [(9.36 x wt) + (726 x ht )] |
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Term
| Physical Activity Factors |
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Definition
Male Female PA (Per Day)
Sedentary 1.0 1.0 Typical daily living activities
Low Active 1.11 1.12 Plus 30-60 min moderate activity
Active 1.25 1.27 Plus 60 min in moderate activity
Very Active 1.48 1.45 Plus 60 min in moderate activity and 60 min vigorous activity or 120 min moderate activity |
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