HKIN 191 Midterm 1 Exam Questions
with Answers
What is the Krebs or citric acid cycle? - Answer-completes the oxidation of substrates
and produces NADH and FADH to enter the electron transport chain
What is the electron transport chain? - Answer-Is a sequence of electron carrier
molecules that shuttle electrons,
down a series of reactions that release energy; used to make ATP.
What is stage 1 of the aerobic system? - Answer--conversion of pyruvate/fatty
acids/amino acids to acetyl-CoA
-one molecule of CO2 is produced
-if protein or fat is converted, an electron is released
What is stage 2 of the aerobic system? - Answer--Acetyl-CoA enters the Krebs cycle
where it undergoes a series of chemical transformations
-molecules of CO2 are generated and electrons are stripped away
-electrons in the form of hydrogen are carried by NAD+ and FAD to inner mitochondrial
membrane
What is stage 3 of the aerobic system? - Answer--electrons are drawn to O2
-energy released by the flow of electrons pumps H+ to the inner mitochondrial
membrane space where they accumulate (stored potential energy)
-stored potential energy transformed into energy used to re-synthesize ATP as H+
passes through ATP synthase
What is oxidative phosphorylation? - Answer-ATP re-synthesis in the aerobic system
What is the fate of lactic acid? - Answer--skeletal muscle uses approx 72% of lactic acid
produced as fuel
-18% is reconverted to glycogen in the liver and muscle
-8% converted to protein
-2% excreted in sweat and urine
What is the capacity and rate of the aerobic system? - Answer-large capacity and slow
rate
How is lactic acid produced? - Answer-if not enough O2 is available to accept H+ and
electrons from NADH, then they are accepted by pyruvic acid to form lactic acid
, What is the role of NAD and FAD? - Answer-both play an important role in the transfer
of electrons - transfer to mitochondria for ATP generation
What energy systems contribute during short term, high intensity activities? - Answer-
anaerobic systems - phosphagen and glycolysis
What is VO2? - Answer-oxygen consumption
What is a MET? - Answer-Metabolic equivalent
1 MET = 3.5 ml/kg/min
What is absolute VO2 max? - Answer-maximum amount of oxygen consumed - L/min
What is relative VO2 max? - Answer-maximum amount of oxygen consumed relative to
body mass - mlO2/kg/min
How do you calculate relative VO2 from absolute VO2? - Answer-divide absolute VO2
by kg
How do you calculate absolute VO2 from relative VO2? - Answer-multiply relative VO2
by kg
How do you calculate relative VO2 from METS? - Answer-multiply METS by 3.5
How do you calculate METS from relative VO2? - Answer-divide relative VO2 by 3.5
How do you calculate total VO2(L) consumed? - Answer-multiply VO2 (L/min) by time
(min)
How do you calculate kcal burned during exercise? - Answer-multiply total VO2
consumed by 5
What is homeostasis? - Answer-maintenance of a constant internal environment
normal resting conditions
What is a steady state? - Answer-the balance between demands placed on the body
and the physiological response to those demands
What is the goal of the control systems of the body? - Answer-to regulate some
physiological variable at or near a constant value
What is a biological control system? - Answer-series of interconnected components that
serve to maintain a physical or chemical parameter at or near a constant
What does a receptor do? - Answer-capable of detecting changes
with Answers
What is the Krebs or citric acid cycle? - Answer-completes the oxidation of substrates
and produces NADH and FADH to enter the electron transport chain
What is the electron transport chain? - Answer-Is a sequence of electron carrier
molecules that shuttle electrons,
down a series of reactions that release energy; used to make ATP.
What is stage 1 of the aerobic system? - Answer--conversion of pyruvate/fatty
acids/amino acids to acetyl-CoA
-one molecule of CO2 is produced
-if protein or fat is converted, an electron is released
What is stage 2 of the aerobic system? - Answer--Acetyl-CoA enters the Krebs cycle
where it undergoes a series of chemical transformations
-molecules of CO2 are generated and electrons are stripped away
-electrons in the form of hydrogen are carried by NAD+ and FAD to inner mitochondrial
membrane
What is stage 3 of the aerobic system? - Answer--electrons are drawn to O2
-energy released by the flow of electrons pumps H+ to the inner mitochondrial
membrane space where they accumulate (stored potential energy)
-stored potential energy transformed into energy used to re-synthesize ATP as H+
passes through ATP synthase
What is oxidative phosphorylation? - Answer-ATP re-synthesis in the aerobic system
What is the fate of lactic acid? - Answer--skeletal muscle uses approx 72% of lactic acid
produced as fuel
-18% is reconverted to glycogen in the liver and muscle
-8% converted to protein
-2% excreted in sweat and urine
What is the capacity and rate of the aerobic system? - Answer-large capacity and slow
rate
How is lactic acid produced? - Answer-if not enough O2 is available to accept H+ and
electrons from NADH, then they are accepted by pyruvic acid to form lactic acid
, What is the role of NAD and FAD? - Answer-both play an important role in the transfer
of electrons - transfer to mitochondria for ATP generation
What energy systems contribute during short term, high intensity activities? - Answer-
anaerobic systems - phosphagen and glycolysis
What is VO2? - Answer-oxygen consumption
What is a MET? - Answer-Metabolic equivalent
1 MET = 3.5 ml/kg/min
What is absolute VO2 max? - Answer-maximum amount of oxygen consumed - L/min
What is relative VO2 max? - Answer-maximum amount of oxygen consumed relative to
body mass - mlO2/kg/min
How do you calculate relative VO2 from absolute VO2? - Answer-divide absolute VO2
by kg
How do you calculate absolute VO2 from relative VO2? - Answer-multiply relative VO2
by kg
How do you calculate relative VO2 from METS? - Answer-multiply METS by 3.5
How do you calculate METS from relative VO2? - Answer-divide relative VO2 by 3.5
How do you calculate total VO2(L) consumed? - Answer-multiply VO2 (L/min) by time
(min)
How do you calculate kcal burned during exercise? - Answer-multiply total VO2
consumed by 5
What is homeostasis? - Answer-maintenance of a constant internal environment
normal resting conditions
What is a steady state? - Answer-the balance between demands placed on the body
and the physiological response to those demands
What is the goal of the control systems of the body? - Answer-to regulate some
physiological variable at or near a constant value
What is a biological control system? - Answer-series of interconnected components that
serve to maintain a physical or chemical parameter at or near a constant
What does a receptor do? - Answer-capable of detecting changes
