Practice Quizzes

Question 0

the synthesis of molecules is called

Answer 0

anabolism

Question 1

in order to contract, muscle cells require

Answer 1

ATP

Question 2

protein synthesis within the cell is regulated by

Answer 2

genes

Question 3

the speed of chemical reactions that occur within the body is regulated by

Answer 3

temperature
pH
enzymes

Question 4

enzymes increase the rate of chemical reactions by _______ the energy of activation

Answer 4

lowering

Question 5

the ability of an enzyme to bind to a particular substrate is determined by

Answer 5

active sites

Question 6

during exercise, the nutrient that is used the least for energy is

Answer 6

proteins

Question 7

the most important carbohydrate for ATP production is

Answer 7

glucose

Question 8

when the initial substrate for glycolysis is muscle glycogen, as opposed to blood glucose,

Answer 8

the net production of ATP is higher

Question 9

how much energy does one gram of fat contain?

Answer 9

9 kcal

Question 10

in order for proteins to be used as substrates they must first be broken down

Answer 10

to amino acids

Question 11

the high-energy phosphate that is the primary source of energy for molecular contraction is

Answer 11

adenosine triphosphate

Question 12

ATP is broken down by the enzyme ATPase to yield

Answer 12

ADP
Pi
energy

Question 13

muscle cells can produce ATP by

Answer 13

creatine phosphate pathway
glycolysis
aerobic metabolism

Question 14

glycolysis produces a net gain of how many ATP molecules per glucose molecule

Answer 14

two

Question 15

what happens to pyruvic acid when there is inadequate O2 available in the mitochondrion

Answer 15

it is converted to lactic acid

Question 16

NAD is reformed from NADH by

Answer 16

shuttling of hydrogens from NADH into the mitochondria

pyruvic acid accepting hydrogens to form lactic acid

Question 17

the chemiosmotic hypothesis describes how

Answer 17

ATP is produced aerobically
ATP is formed via hydrogen ion diffusion
hydrogen ions are pumped across the inner mitochondrial membrane

Question 18

which of the following is not produced in the Krebs cycle

Answer 18

lactate

Question 19

the two anaerobic metabolic pathways are the

Answer 19

ATP-PC system and glycolysis

Question 20

the majority of electrons that enter the ETC comes from

Answer 20

NADH and FADH formed in the Krebs cycle

Question 21

the aerobic metabolism of one molecule of glucose results in a net gain of

Answer 21

32 ATP

Question 22

phosphocreatine breakdown is regulated by

Answer 22

creatine kinase

Question 23

important regulatory enzymes in carbohydrate metabolism are

Answer 23

phosphofructokinase and phosphorylase

Question 24

metabolic pathways that produce ATP are generally inhibited by high levels of

Answer 24

ATP

Question 25

at rest, the VO2 is approximately ________ mL/kg/min

Answer 25

3.5

Question 26

which group of activities use energy derived predominately from the ATP-PC system?

Answer 26

gymnastics vault, softball pitch, high jump

Question 27

the upward drift of VO2 during steady state exercise is primarily due to

Answer 27

increasing body temperature

Question 28

the physiological factors that influence VO2 max are

Answer 28

the delivery of oxygen to the muscle the uptake and use of oxygen by the muscle genetics and exercise training

Question 29

a factor that contributes to excess post exercise oxygen consumption is

Answer 29

resynthesis of creatine phosphate in muscle

Question 30

the rise in blood lactic acid concentration above the lactate threshold can occur due to

Answer 30

an increase in lactic acid production and a decrease in lactic acid removal

Question 31

during low-intensity exercise (<30%), the primary fuel source for muscle is

Answer 31

fats

Question 32

in prolonged (3-4 hours) moderate-intensity exercise, there is an increased reliance on

Answer 32

blood sources of carbohydrates and fat

Question 33

the shift from fat to carbohydrate metabolism is regulated by

Answer 33

the type of fiber recruited

Question 34

the primary determinant of plasma FFA oxidation during exercise is

Answer 34

the blood level of the fuel

Question 35

the RQ for fat is

Answer 35

equal to VCO2/VO2

Question 36

during the first hour of submaximal exercise, most of the carbohydrate metabolized comes from

Answer 36

muscle glycogen

Question 37

the mobilization of the free fatty acids into the blood is inhibited by

Answer 37

lactic acid

Question 38

fatigue results after depletion of carbohydrate stores due to the reduction

Answer 38

of Krebs cycle intermediates