The primary function of the electron transport chain is to ____.
shuttle electrons from NADH and FADH to rephosphorylate ATP
Which of the following respiratory exchange ratio (RER) values would indicate metabolism of pure fat?
0.70
The most important carriers for electrons in oxidation-reduction reactions are ____.
NAD and FAD
The major function of the Krebs cycle portion of oxidative phosphorylation is to produce moderate to large amounts of ATP.
False
Long distance running would depend primarily on the creatine phosphate system as a source of ATP.
False
The fastest and least complex energy system used to produce ATP is ____.
creatine phosphate
The average O2 max for young adults is approximately _____ ml/kg/min.
35-40 for females and 40-45 for males
ATP and CrP are both high-energy phosphate compounds.
True
The duration of the anaerobic glycolysis energy system is approximately ____.
1-2 minutes
The branched chain amino acids can be relatively easily metabolized by skeletal muscle but they are considered the least preferred fuel source when compared to carbohydrates and fats.
True
An increased utilization of the aerobic energy system results in a(n) ____.
increase in the amount of oxygen consumed and the amount of carbon dioxide produced.
The net (final) ATP production from anaerobic glycolysis is ____.
3 ATPs if beginning with glycogen
It is biochemically impossible to convert carbohydrate to fatty acids.
False
When alcohol consumption is high, the primary pathway for the metabolism of alcohol is the ____.
microsomal ethanol-oxidizing system (MEOS)
Why does the amount of ATP produced in skeletal muscle differ from the amount produced in other tissues?
Skeletal muscle transfers electrons via FAD while other tissues use NAD.
As exercise intensity increases, the percentage of energy from fat metabolism decreases.
True
The body's "turnover"of creatine is approximately ____ per day.
2 g
An RER of 1.0 means that 100% of the fuel used is derived from fat and 0% is derived from carbohydrate.
False
How many chemical steps are required for the rephosphorylation of ATP by creatine phosphate?
1
Free radicals (molecules with unpaired electrons) are most likely to occur during ____.
oxidative phosphorylation
Exercising muscle prefers to use glycogen rather than glucose because the net yield of ATP is greater.
True
Oxidative phosphorylation is a process that begins with glucose and ends with lactate.
False
Most research has shown that short-term creatine "loading" results in an immediate increase in absolute, maximal power.
False
Which of the following is a true statement regarding the function of creatine phosphate (CrP)?
CrP rapidly replenishes ATP.
What is creatine phosphate (CrP)?
A nitrogen-containing compound made from certain amino acids
The purpose of the three energy systems is to use chemical energy to re-form ATP.
True
Metabolism of one molecule of which of the following produces the highest number of ATPs?
Fat metabolism (e.g., palmitate)
The body restores its immediate source of energy by the rephosphorylation of ____.
ADP
Oxidative phosphorylation is the predominant energy system used at rest.
True
Oxidative phosphprylation is the preferred energy system during ____.
dance aerobics
Anaerobic glycolysis is the preferred energy system during ____.
sustained, repeated sprints
Even under severe conditions during exercise, protein metabolism makes up at most approximately _____% of total energy expenditure.
10
Creatine phosphate is the preferred energy system during ____.
short, fast sprints
The rephosphorylation of ATP is an exergonic reaction.
False
Which of the following is a true statement about nutrient metabolism in the starvation state?
CNS depends primarily on ketones.
The purpose of beta-oxidation is to ____.
remove two-carbon segments from fatty acids and convert them to acetyl CoA
Why is there a difference between the amount of ATP produced by glucose and by glycogen?
The breakdown of glycogen requires less ATP in the energy investment phase.
Highly aerobic muscle fibers and other tissues can use lactate as an energy source.
True
If creatine phosphate is nearly depleted in skeletal muscle by high-intensity exercise, approximately how long does it take to restore creatine phosphate levels?
1-2 minutes
The energy system that has the slowest rate of ATP replenishment is oxidative phosphorylation.
True
In the electron transport chain of oxidative phpsphorylation, the final electron acceptor is ____.
oxygen
The rate of glycolysis in muscle is controlled primarily by ____.
phosphofructokinase (PFK)
Beta-oxidation is a process associated with the breakdown of amino acids for energy.
False
Once pyruvate is converted to lactate in the muscle it cannot be converted back.
False
The term aerobic energy system refers to ____.
oxidative phosphorylation
Which of the following is a true statement about nutrient metabolism in the fasting state?
Liver glycogen is depleted.
The postabsorptive state refers to the 3- to 4-hour period after food is eaten.
False
Which of the following statements regarding energy systems is false?
One system is switched on while the others are switched off.
Anaerobic glycolysis is an energy system that uses ____.
carbohydrate only
Which of the following statements regarding ATP is true?
ATP stores potential energy in its phosphate bonds.
The greatest influence on maximal oxygen consumption is ____.
aerobic exercise training
The elevated oxygen consumption during recovery from an exercise bout is called EPOC or ____.
oxygen debt
Fast-twitch muscle fibers are also called glycolytic because of their reliance on anaerobic energy systems.
True
Creatine supplements are effective for both strength and endurance athletes.
False
If creatine phosphate is nearly depleted in skeletal muscle by high-intensity exercise, how is it rephosphorylated?
From ATP generated aerobically by oxidative phosphorylation
The primary function of the Krebs cycle is to ____.
oxidize carbohydrates, fats, and proteins and ready them for ATP production
The process of giving up electrons is called ____.
oxidation
The relationship between oxygen consumption and exercise intensity is linear until maximum oxygen consumption is reached.
True
The respiratory exchange ratio (RER) is a way of determining the body's metabolism of ____.
carbohydrate and fat
Why is pyruvate considered a "key glycolytic compound"?
It can be metabolized either anaerobically or aerobically.
VO2 max
maximal oxygen consumption
RER
ratio of carbon dioxide production to oxygen consumption
Oxidized
has given up electrons
Insulin
helps regulate carbohydrate metabolism
Lipolysis
breakdown of triglycerides
Lactate
end product of glycolysis
Reduced
has accepted electrons
Alanine
an amino acid that can be oxidized
Glycogenolysis
breakdown of glycogen
Palmitate
a fatty acid that can be oxidized
Based on dietary intake only, whom would you expect to have the lowest amount of muscle creatine?
Vegetarians
Anaerobic production of ATP can occur in the ____.
cytoplasm/sarcoplasm via glycolysis
The respiratory exchange ratio (RER) uses the amount of carbon dioxide produced and the amount of oxygen consumed to determine the percentage of energy derived from carbohydrate and fat.
True
Oxygen deficit and oxygen debt are interchangeable terms that describe the "lag time" that exists between the onset of aerobic exercise and the ability of the aerobic energy system to achieve its full capacity.
False
When an individual is in a fed state (the time when nutrients are being absorbed), which hormone exerts the most influence?
Insulin
The energy source preferred by exercising muscle for the process of anaerobic glycolysis is ____.
glycogen
Transamination and deamination refer to the metabolism of ____.
proteins
When alcohol (ethanol) is consumed at low to moderate levels, the primary pathway is the alcohol dehydrogenase (ADH) pathway.
True