Exam 1 Flashcards
(24 cards)
Define the terms energy, energetics, bioenergetics, biological work, and thermodynamics.
Thermodynamics is the study of energy and its effects on matter.
Bioenergetics is the quantitative analysis of how organisms gain and utilize energy, a special part of thermodynamics.
Energy is the ability to do work.
Energetics is the branch of science dealing with the properties of energy and the way in which it is redistributed in physical, chemical, or biological processes.
Biological Work is synthetic work, mechanical work, electric work, concentration work, heat production, bio-luminescence.
List and describe the forms of energy (e.g., light energy), the forms of biological work (e.g., muscle contraction), and the first and second laws of thermodynamics.
Forms of energy include Chemical, Mechanical, Heat, Light, Electric, and Nuclear
Biological work in humans include Mechanical work, chemical work, and transport work used for digestion, muscle contraction, nerve transmission, circulation, tissue synthesis, and glandular synthesis
The first law, also known as Law of Conservation of Energy, states that energy cannot be created or destroyed in an isolated system.
The second law of thermodynamics states that the entropy of any isolated system always increases.
List and describe the usable and storage forms of macronutrients used for energy production during exercise including carbohydrates (e.g., glucose and glycogen), fats (e.g., free fatty acid, stearic acid, triglyceride).
Fats (lipids) - fuel, energy storage, cell membrane, hormones e.g. milk, dairy, eggs, nuts, meat. Storage form -
Adipose tissue 107,800 kcal
Muscle triglycerides 3,850 kcal
Carbohydrates - energy storage, cell membrane, DNA, RNA e.g. cereals, wheat (bread), potato, pasta & rice. Storage form -
2K Diet Mixed
Muscle glycogen 1,400 kcal
Liver glycogen 240 kcal
Blood glucose 40 kcal
3K Diet
Muscle glycogen 2,400 kcal
Liver glycogen 360 kcal
Blood glucose 40 kcal
Proteins - structure (muscles, bones, cells, skin), transport, enzymes, protective e.g. meat, fish, dairy.
Water - medium for biochemical reactions, transport, excretion, lubrication e.g. beverages, fruit, vegetables.
Describe the role of enzymes (e.g., ATPase) and coenzymes (e.g., NADH) in biological reactions (endergonic and exergonic) including oxidation-reduction reactions.
Enzyme is a molecule that catalyzes biochemical reactions in a living organism, usually a protein; facilitate metabolic pathways for increase the reaction rate without raising the temperature-Biological catalysts-Speed up the rate of a chemical reaction without being permanently changed in the process-Proteins: tertiary and/or quaternary structure-Each enzyme works on a specific molecule called the substrate (or substrates)-Each enzyme catalyzes only one type of reaction
Coenzyme is a non protein substance that is associated with and activates an enzyme as a an organic cofactor-needed by apnoenzyme to be activated forming holoenzyme. ex. NAD+, NADP+
Endergonic example happens after ATP donates a phosphate group to a coupled reaction, then it becomes ADP. The ADP can be recharged in an endergonic reaction to form ATP.
Exergonic example would be the breakdown of glucose to carbon dioxide and water for cellular respiration.
Oxidation-reduction reactions transfer electrons from one molecule to another.
Coupled reactions are reactions in which an exergonic reaction drives an endergonic reaction.
Describe the structure and role of ATP (and other high energy compounds) in energy transfer and explain the amount of energy released from ATP in the body.
Structure of ATP-nucleotide consisting of a nitrogen-containing base, a sugar, and at least one phosphate group.
Role of ATP-The role of ATP is to act as an intermediate. It transfers energy from “high energy molecules” to lower energy molecules. Energy released from ATP is used for muscle contraction.
Adenosine Triphosphate and Adenosine Diphosphate. The first is the currency of the body. It allows high energy to be released when a phosphate bond is broken by hydrolysis. ATP -> ADP + Pi + Energy
ATPase used for breaking ATP apart
ADP, Pi (a phosphate group) and 30.5 kJ energy.
Identify the bioenergetic pathways (energy systems) used during exercise including the phosphagen system (ATP-CP system), the lactic acid system (glycolytic metabolism), and the aerobic system (oxidative metabolism).
- phosphagen system/phosphocreatine system (anaerobic)-rate limiter creatine kinase; chemical fuel
- lactic acid system/glycolysis (anaerobic)-rate limiter phosphofructokinase; carbohydrate fuel
- Krebs cycle (aerobic)-in the mitochondria; rate limiter isocitrate dehydrogenase; carbs(pyruvate)/fat/protein fuel
- electron transport chain (aerobic)-in the mitochondria; rate limiter cytochrome oxidase; carbs(pyruvate)/fat/protein fuel
Overview the energy systems and describe their roles in providing energy to resynthesize ATP based on the intensity and duration of the exercise performed.
Anaerobic
-Formation of ATP by phosphocreatine (PC) breakdown. Short term intense exercise. Catalyzed by creatine kinase, donation of a phosphate group and its bond energy from PC to ADP to form ATP.
PC + ADP -> ATP + C
-Glycolysis is an anaerobic pathway used to transfer bond energy from glucose to rejoin Pi to ADP and convert to pyruvate or lactic acid.
Aerobic
Occurs inside the mitochondria and involves the interaction of two metabolic pathways:
1. Krebs cycle: Pyruvate is broken down into Acetyl-CoA and remaining carbon is given off as CO2. Acetyl-CoA is combined with oxaloacetate to form citrate. Each molecule of glucose results in two turns of Krebs cycle. Primary function is to remove hydrogens and energy associated from substrates involved - 1 FADH and 3 NADH
2. Electron Transport Chain: Electrons removed front the FADH and NADH are passed down a series of electron carriers known as cytochromes.
Describe the phosphagen system (ATP-CP system) with regard to: (1) the specific method of ATP production, (2) the fuel used, (3) the reason it fatigues, (4) its capacity (total amount of ATP made in moles) and power (rate at which ATP is made in moles/min), (5) its enzyme regulation, and (6) the types of activities for which it is the predominant source of ATP (e.g., 100 m run).
-
CP –> C+ P+ Energy
Creatine kinase - Chemical Fuel (creatine phosphate)
- The lactate produced through this system will
accumulate unless there is oxygen available
to break it down. As the lactate accumulates
it changes the acidity of the blood, reducing
the efficiency of muscle contraction, causing
muscle fatigue. Therefore, this system can
only be used maximally for 1-2 minutes before
requiring recovery. A recovery time of
approximately 8 minutes will aid the removal of
lactate from the muscles and also give time to
replace the glycogen stores in the muscles. - Capacity = 1.0 mole ATP (30 kg muscle mass)
(10 kcal). Power = 1 mol / 15 sec = 4 mol / min. - Regulation: Creatine kinase (CK) and Adenosine triphosphatase (ATPase)
- Activities resulting in fatigue in up to 15-20 sec
Running -up to 200 m
Swimming -up to 50 m
Track (100m, 200m) & Field (jumps, throws)
Sprinting, jumping, throwing in many sports
Describe the lactic acid system with regard to: (1) the specific method of ATP production including the individual reactions of glycolysis, (2) the sources of fuel (blood glucose and muscle glycogen), (3) the by-products made and the reason it fatigues, (4) its capacity and power, (5) its enzyme regulation, and (6) the types of activities for which it is the predominant source of ATP (e.g., 400 m run).
- In Step 7 (at Rearrangement of 3-Phosphoglycerate) and 10 (formed again as we add a phosphate to phosphoenolpyruvate from ADP).
- Useable form -Glucose(simple sugar)
Storage form -Glycogen (muscle / liver) - Pyruvate and H+
- Capacity: 1 Glucose + 3 ADP + 3 P + Energy 2 Lactate + 2 H2O + 3 ATP (1.5 mol reality)
Power = 1.5 mole / 45 sec = 2.0 moles/min
(20 kcal/min)
1 mol / 1.5 moles
Can maximally tolerate only 90 g of lactate (1 mole) - Regulations: Phosphorylase (Glycogenolysis)
Stimulated:
High [ADP], [P]
High [calcium]
High [epineph]
(Exercise)
Inhibited:
High [ATP]
(Rest)
Phosphofructokinase (Glycolysis)
Stimulated:
High [ADP], [P]
High [fructose P]]
Low [CP]
(Exercise)
Inhibited:
High [ATP]
High [citrate]
High [FFA]
High [CP]
(Rest) - Activities resulting in fatigue in 45-90 sec
Running -400 to 800 m
Swimming -100 to 200 m
Track (400m, 800m, 400m hurdles, 4 x 400m)
Overview the multiple pathways involved in the production of ATP through the aerobic system including: (1) slow glycolysis, (2) fat oxidation, (3) protein catabolism, (4) the Krebs cycle, and (5) electron transport chain.
- slow glycolysis 38-39 ATP made - glucose oxidation in order to obtain ATP
- fatty acid β-oxidation 147 ATP made- fatty acids breakdown into acetyl-CoA, to be used by the Krebs’ cycle.
- protein catabolism breakdowns proteins into pyruvate, acetyl CoA, acetoacyl CoA, oxaloacetate, and α-ketoglutarate, amino acids can serve as a source of energy production through the Krebs cycle.
- citric acid cycle (Krebs’ cycle) 12 ATP made - acetyl-CoA oxidation in order to obtain GTP and valuable intermediates.
- ETC 34 ATP made
Explain the differences between slow and fast glycolysis with specific regard to the end products made (i.e., lactate, pyruvate, NADH).
Main outcome is how much ATP you can get out of it. In slow glycolysis with glucose as starting product you can get 32 ATP (with glycogen 33 ATP). In fast glycolysis with glucose as starting product 2 ATP (with glycogen 3 ATP). The purpose for this difference is so that our body is not over working itself if not all the ATP is going to get used.
Slow glycolysis end product = Acetyl CoA (If oxygen IS available)
Fast glycolysis end product = Lactate/ Lactic Acid (When NO oxygen is available)
Describe the Krebs cycle (reactions involved, by-products) and explain its role in providing electrons for the electron transport chain.
The primary function of the Krebs cycle is to remove hydrogens, using NAD and FAD as hydrogen carriers. As a result, NADH and FADH are formed
At (step 3 before krebs cycle) acetyl group binds to Coenzyme A. A reaction occurs and 2 carbons from the acetyl group are passed on to the krebs cycle
Step 4 - these 2 carbons join with a 4-c (carbon) compound to produce Citric Acid (krebs cycle begins)
Step 5 - A series of reactions occur, step by step the carbon atoms wind up as CO2, electrons are accepted, forming NADH, FADH2, and ATP
Step 5 (reactions) -
a). the CO2 is released as waste
b). the 3 NADH and the 1 FADH2 are used in the next step
c). 1 ATP is formed
Describe the electron transport chain and explain its role regarding the flow of electrons, the concentration of protons, and the process of oxidative phosphorylation.
It is the last stage of Cellular Respiration.
Glycolysis generates high-energy electrons that are passed to NAD+, forming NADH. Those NADH molecules can enter the Mitochondrion, where they join the NADH and the FADH2 generated by the Krebs Cycle. The electrons are then passed from all those carriers to the Electron Transport Chain. The Electron Transport Chain then uses the high-energy electrons from Glycolysis and the Krebs Cycle to convert ADP to ATP.
by the flow of protons down the electrochemical gradient across a membrane thats impermeable to ions
energy released by electron transport is used to transport protons against the electrochemical gradient
- reduced substrates (NADH/FADH2) donate e- to 1st protein and pass it along to 3 other proteins inside mitochondrial matrix
- e- goes to O2 electron acceptor, this pushes protons to intermembrane space
- energy stored as electrochemical potential
- ATP synthase takes ADP and Pi, then generates ATP using the passive flow of H+
Oxidative phosphorylation is the process by which ATP is formed as a result of the transfer of electrons from NADH and FADH₂ to O₂ by a series of electron carriers.
Further describe the aerobic system with regard to: (1) the sources of fuel (carbohydrate, fat), (2) the by-products made and the reason it fatigues, (3) its capacity and power, (4) its enzyme regulation, and (5) the types of activities for which it is the predominant source of energy (e.g., 1500 m run).
- Can use all types of food fuels (CHO, FAT, PRO)
- Carbon dioxide and H2O.
- Capacity based on glycogen depletion - max is at least 95 moles. Power 15 kcal/min / 10 kcal/mole = 1.5 moles/min
- phosphofructokinase (PFK) at step 3 and phosphorylase to turn glycogen into glucose
- Activities resulting in fatigue in more than 3 to 5 min
Running -1500 m and longer (marathon)
Swimming -400 m and longer (triathlon)
Track (1500 m, 1 mile, 5000 m, 10,000 m)
Cycling -long distance
Rowing -long distance
Identify the sources of ATP production in aerobic metabolism and explain the total amount of ATP made (in moles) from 1 mole of glucose and from 1 mole of stearic acid.
ATP is produced in the mitochondria (via the Krebs cycle) and it produces 38-39 mols of ATP (34 ATP in the ETC) of ATP per 1 mol of glucose and 147 mols ATP (139 ATP in the ETC) per 1 mole of stearic acid.
Define the respiratory exchange ratio (RER) with regard to carbon dioxide production (VCO2) and oxygen uptake (VO2) and explain how it can be used to identify the contributions from fat and carbohydrate metabolism during exercise
RER = CO2Production / O2Uptake
RER = VCO2/ VO2
RER = 0.21 L/min / 0.30 L/min = 0.70
RER = 2.50 L/min / 2.50 L/min = 1.00
100% Stearic Acid Use
RER = 18 CO2/ 26 O2= 0.70
100% Glucose Use
RER = 6 CO2/ 6 O2= 1.00
At RER 0.7 100% Fat and 0% CHO
At RER 0.85 50% Fat and 50% CHO
At RER 1.0 0% Fat and 100% CHO used
Describe and explain the transition from low to high intensity exercise with regard to the conditions in the muscle (e.g., rise in ADP) and how this affects the energy system and source of fuel being used (especially fat versus carbohydrate).
Maximum Rapid increase in [ADP] & [P] Phosphagen - PC
High Increase in [ADP] & [P] Lactic acid - CHO
Moderate Increase in [ADP] & [P] Aerobic - CHO (75%)
Low Slow increase in [ADP] & [P] Aerobic - Fat (67%)
Rest High resting [ATP] in muscle Aerobic - Fat (100%)
Graph the response of oxygen uptake (VO2) to rest, a short bout of high intensity exercise, and recovery, and identify the oxygen deficit and excess post-exercise oxygen consumption (EPOC). Explain the role of EPOC in the recovery process.
https://www.google.com/search?q=epoc+graph+explained&rlz=1C1CHZL_enUS688US689&sxsrf=ACYBGNQ1f4j78f-ty59x8nHXNpAPKju9Xg:1570475990167&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj0r5b87orlAhVCsp4KHR4QDmQQ_AUIEigB&biw=1355&bih=620#imgrc=Hbp2mQ6XaTkNjM:
Define recovery from exercise, identify the time course of recovery, and explain the following components of the recovery process: (1) restoration of muscle phosphagen, (2) removal of blood lactate, and (3) restoration of muscle glycogen.
Recovery-The process by which the body is restored back to “pre-exercise” conditions
Recovery from High Intensity Exercise
Oxygen deficit
Excess post-exercise oxygen consumption (EPOC)
- Phosphagen Restoration (minutes)
Aerobic production of ATP (Aerobic System) restores ATP in
skeletal muscle
Continued production of ATP provides energy to
phosphorylate creatine and restore CP in skeletal muscle - Lactic Acid Removal (hours)
Most is oxidized to pyruvic acid and consumed (60-65%)
Some is used to reform glycogen and stored (20-25%)
Some is used to form amino acids and stored (10-15%)
A small amount is directly excreted in urine (up to 5%)
Active recovery cuts lactic acid removal time in half
Especially important for repeated bouts of exercise
- Recovery from Prolonged Exercise
Glycogen Restoration (days)
High CHO intake can cut glycogen restoration time in half
Identify the methods by which lactic acid is removed from the muscle during recovery (e.g., converted to acetyl groups and consumed as a source of fuel). Compare the rates of lactic acid removal using a passive, rest recovery compared to an active, exercise recovery.
Most is oxidized to pyruvic acid and consumed (60-65%)
Some is used to reform glycogen and stored (20-25%)
Some is used to form amino acids and stored (10-15%)
A small amount is directly excreted in urine (up to 5%)
Active recovery cuts lactic acid removal time in half
Especially important for repeated bouts of exercise
High CHO intake cuts glycogen restoration in half.
Describe and explain the restoration of muscle and liver glycogen stores with respect to the type of nutrients consumed during recovery (e.g., simple sugars) and the time course of restoration.
Compare and contrast the characteristics of the three energy systems with regard to their: (1) need for oxygen, (2) fuel sources, (3) by-products, (4) capacity and power, and (5) types of activities for which they provide energy. Discuss the advantages and disadvantages of each system.
1.
2.
3.
4.
5.
Illustrate the concept of the energy continuum demonstrating the transition from the use of anaerobic energy systems for short duration, maximal intensity exercise to the use of the aerobic system for long duration, moderate intensity exercise. Identify on the illustration times to fatigue (e.g., 10 sec, 30 sec, etc.) and the location of specific sports and/or activities (e.g., 100 m run, basketball, 400 m swim, etc.).
Phosphagen System:
0% Aerobic and 100% Anaerobic
1-3 seconds (weight lifting)
10% Aerobic and 90% Anaerobic
10 seconds (football)
Lactic Acid (Fast Glycolysis)
20% / 80%
30 secs (Basketball)
30% / 70%
1 min (100 swim)
40% / 60%
2 min (soccer)
50% / 50%
(200 m swim)
Aerobic
60% / 40%
4 min (400 m swim)
70% / 30%
80% / 20%
90% / 10%
30 min (10K)
100%
120 min (Marathon)
Describe the adaptations in the energy systems as a result of sprint (high intensity interval) training and endurance (moderate intensity continuous) training. Include specific values describing maximal oxygen uptake (VO2max) in trained and untrained persons.
Phosphagen System:
Capacity: 25-40% Fuel Storage / ATP 25% CP 40%
Power: 20-35% Enzymes / CK 30-35% ATPase 30%
Lactic Acid System:
Capacity: Increased buffering / neutralization of lactic acid (hydrogen ion)
Power: Increase phosphofuctokinase (30-50%). Increase phosphorylase (50-60%)
Aerobic System:
Capacity: Muscle glycogen (50-250%) and triglycerides (100-150%)
Power: Increase blood and oxygen (VO2max) and Increase myoglobin (O2 diffision).
Most Anaerobic Adaptations (>85% VO2max) for sprint training which is high intensity. 45-90 sec duration of exercise and 2-3 times longer recovery that uses fast twitch muscles. Moderate intensity is 45-90 mins exercise for slow twitch muscle cells (using 75-85% VO2max).
