Chapter 5: Fundamentals of Human Energy Transfer Flashcards
What are the 4 Macronutrients present in the Human body?
- Fats 2. Proteins 3. Carbohydrates 4. Water
What is the 1st Law of Thermodynamics?
Conservation of Energy (energy can neither be created nor destroyed–but can be transformed from one form to another w/o being depleted)
________ and ________ constitute the total energy of a system.
- Potential - Kinetic
_________: any physical or chemical process that releases energy to its surroundings.
- Exergonic (Represent “downhill” processes; they produce a decline in free energy)
__________ : Chemical processes store or absorb energy
- Endergonic (Represent “uphill” processes, and proceed with an increase in free energy for biologic work)
What is the 2nd Law of Thermodynamics?
- Tendency of potential energy to convert to kinetic energy of motion with a lower capacity for work - Ultimately, all of the potential energy in a system degrades to the unusable form of kinetic or heat energy
What are the 6 forms of energy in the human body?
- Chemical 2. Mechanical 3. Heat 4. Light 5. Electric 6. Nuclear
What are the 3 most relevant forms of energy in the body?
- Chemical 2. Mechanical 3. Heat
What are the 3 different forms of biologic work?
- Mechanical Work 2. Chemical Work 3. Transport Work
What is mechanical work?
- Muscle contraction.
What is chemical work?
- Synthesis of cellular molecules.
What is transport work?
- Concentration of various substances in the intracellular and extracellular fluids.
What are (4) factors that affect Bioenergetics?
- Enzymes 2. Reaction rates 3. Mode of Action 4. Coenzymes
________: highly specific and large protein catalyst that accelerates the forward and reverse rates of chemical reactions within the body without being consumed or changed in the reaction.
- Enzymes
__________ : operation rate of enzymes
- Reaction Rates
___________: How an enzyme interacts with its specific substrate
- Mode of Action
___________ : Complex nonprotein that facilitate enzyme action by binding the substrate with its specific enzyme
- Coenzymes
ATP–cells’ 2 major energy-transforming activities:
- Form and conserve ATP from food’s potential energy 2. Use energy extracted from ATP to power all forms of biologic work
The body can store only __ to ___ of ATP.
80 - 100 * Represents an additional advantage due to its molecule’s heaviness * Because cells store only a small quantity of ATP, it must be resynthesized continually at its rate of use
Phosphocreatine or PCr provides some energy for: ____ _________
-ATP Resynthesis
The hydrolysis of PCr begins at the onset of intense exercise, does not require oxygen, and reaches a maximum in: __-_____
-8 to 12 seconds
Cells store _____ in considerably larger quantities than ATP
-PCr
ATP and PCr are considered _______ sources of Phosphate-bond energy
-Anaerobic
________ occurs on the inner lining of mitochondrial membranes.
-Oxidation
_________ involves the transferring of electrons from NADH and FADH2 to molecular oxygen–which release and transfer chemical energy to combine ATP from ADP plus a Phosphate ion.
-Oxidation
During ______ ATP Resynthesis, oxygen combines with hydrogen to form water.
-Aerobic
Water us formed in the _____.
-ETC (Electron Transport Chain)
Oxidative-Phosphorylation creates ___ ATP.
-3
Name at least (4) Macronutrient Fuel Sources for Oxidation.
-Triacylglycerol & glycogen molecules stored w/in muscle cells -Blood Glucose -Free Fatty Acids -Intramuscular- and liver-derived carbon skeletons of amino acids -Anaerobic reactions in the cytosol in the initial phase of glucose or glycogen breakdown -Phosphorylation of ADP by PCr under enzymatic control by creatine kinase and adenylate kinase
What is the primary function of carbohydrates?
-Supply energy for cellular work.
What is the only macronutrient whose potential energy generates ATP aerobically?
-Carbohydrates
The complete breakdown of one mole of glucose to carbon dioxide and water yields a maximum of _____ of chemical free energy available for work.
-686 kCal
Oxidation of one glucose molecule in skeletal muscle yields a total of how many ATP molecules?
-32
Glycolysis is:
-Carbohydrate breakdown
________: Relatively slow process resulting in substantial ATP formation–The second stage of carbohydrate breakdown converts pyruvate to acetyl–CoA, which then progresses through the citric acid cycle.
-Aerobic
________: Rapid but limited ATP production that produces lactate as the end product
-Anaerobic
What is depicted in the diagram below?
-Glycolysis
What process is depicted in the diagram below?
-Lactate Formation
The combined process of Glycolysis, Citric Acid Cycle, and the Electron Transport Chain yield how many net ATP?
-32
____ _____ is the most plentiful source of potential energy.
-Stored Fat
What are 3 specific energy sources for fat catabolism?
(1) Triacylglycerols stored directly within the muscle fiber in close
proximity to the mitochondria.
(2) Circulating triacylglycerols in lipoprotein complexes that become
hydrolyzed on the surface of a tissue’s capillary endothelium.
(3) Adipose tissue that provides circulating free fatty acids mobilized
from triacylglycerols in adipose tissue.
The breakdown of a triacylglycerol molecule yields about ____ molecules of ATP.
-460
Protein can serve as an _____ _______.
-Energy substrate
When deamination removes nitrogen from an amino acid molecule,
the remaining carbon skeleton can enter metabolic pathways to
produce ATP ________.
-Aerobically
Protein acts as an energy substrate during long duration, __________
activities.
-endurance-type
