Ch 4 - Metabolism

Question 1

Bioenergetics

Answer 1

study of energy in the body and how it gets transformed into usable forms through chemical reactions

Question 2

Metabolism

Answer 2

chemical reactions that occur in the body for it to maintain itself; process of nutrients being acquired, transported, used, and disposed of

Question 3

Exercise metabolism

Answer 3

bioenergetics related to physiologic changes and demands placed on body during exercise

Question 4

Substrates

Answer 4

material on which enzyme acts; carbohydrates, protein, fat (lipids)

Question 5

Carbohydrates

Answer 5

top source of energy; eventually becomes glucose; includes sugars and starches

Question 6

Glucose

Answer 6

simple sugar manufactured by body; end result after digestion of carbs; main source of fuel

Question 7

Glycogen

Answer 7

form of carbs stored in liver and muscle cells; string of glucose molecules; can be quickly broken into glucose and used as energy

Question 8

Fat

Answer 8

one of the 3 main substrates; used as energy source in prolonged exercise

Question 9

Triglycerides

Answer 9

chemical form of fat; how calories that aren’t needed are stored in fat cells

Question 10

Protein

Answer 10

amino acids linked by peptide bonds; used to build and repair soft tissue; only used as energy in starvation

Question 11

Gluconeogenesis

Answer 11

formation of glucose from non-carb sources

Question 12

Adenosine triphosphate (ATP)

Answer 12

energy storage and transfer unit in cells; where source of immediate energy is stored

Question 13

Adenosine diphosphate (ADP)

Answer 13

compound from which ATP is formed; what’s left behind when ATP bonds are broken to release energy

Question 14

Rigor

Answer 14

muscle state when ATP is depleted and there’s no energy to break the connection between cross-bridges and active actin sites

Question 15

ATPase

Answer 15

enzyme that combines with an ATP molecule and splits the last phosphate group away to release free energy

Question 16

Pi

Answer 16

phosphate molecule remaining along with ADP after the last phosphate group is split away

Question 17

Phosphorylation

Answer 17

process by which a phosphate group is added back to ADP, so ATP can release energy again

Question 18

Phosphocreatine

Answer 18

molecule from which a phosphate is transferred to an ADP molecule

Question 19

Phosphagen

Answer 19

ATP + CP

Question 20

ATP-PC system

Answer 20

creates new ATP molecule from a PC molecule; simplest and fastest system; anaerobic; for high-intensity, short-duration exercise; always used at onset of activity

Question 21

Glycolysis

Answer 21

anaerobic process of producing ATP through breakdown of glucose

Question 22

Pyruvic acid

Answer 22

byproduct of aerobic glycolysis

Question 23

Lactic acid

Answer 23

byproduct of anaerobic glycolysis

Question 24

Oxidative system

Answer 24

aerobic progess to generate ATP; made up of aerobic glycolysis, Krebs cycle, electron transport chain; used for sustained exercise and at rest; uses fat; can last an indefinite amount of time

Question 25

Acetyl CoA

Answer 25

what pyruvic acid converts to in the presence of oxygen

Question 26

Electron transport chain

Answer 26

hydrogen ions released in glcolysis and Krebs cycle combine with other enzymes and provide energy for oxidative phosphorylation of ADP to form ATP

Question 27

B-oxidation

Answer 27

first step in oxidation of fat; breakdown of triglycerides to form free fatty acids, which convert into acetyl CoA molecules

Question 28

Steady-state exercise

Answer 28

performed at constant intensity

Question 29

Excess post-exercise oxygen consumption

Answer 29

elevation of metabolism after exercise

Question 30

Recovery

Answer 30

an aerobic event to set ATP-PC back toward normal and eliminate lactic acid

Question 31

Respiratory quotient

Answer 31

CO2 expired / O2 consumed; 100% carbs at 1.0, 100% fat at 0.85

Question 32

Fat-burning zone

Answer 32

myth that low-intensity exercise burns more fat because greater energy comes from fat than carbs - but it has lower caloric expenditure, including calories from fat