Ch 8 Exercise Metabolism and Bioenergentics

Question 1

Adenosine triphosphate (ATP)

Answer 1

A high-energy molecule that serves as the main form of energy in the human body; known as the energy currency of the body.

Question 2

Bioenergetics

Answer 2

The study of energy in the human body.

Question 3

First law of thermodynamics

Answer 3

Energy cannot be created or destroyed but merely converted from one form to another.

Question 4

Substrates

Answer 4

Intermediate forms of nutrients used in metabolic reactions to create adenosine triphosphate.

Question 5

Glucose

Answer 5

The simplest form of carbohydrate used by the body for energy.

Question 6

Glycogen

Answer 6

Glucose that is deposited and stored in bodily tissues, such as the liver and muscle cells; the storage form of carbohydrate.

Question 7

Ventilatory threshold 1 (VT1)

Answer 7

The point at which the body uses an equal mix of carbohydrate and fat as fuel sources.

Question 8

Ventilatory threshold 2 (VT2)

Answer 8

The point where glucose provides nearly all of the energy for the activity.

Question 9

Fats

Answer 9

One of the three main classes of foods and a source of energy in the body.
Fats help the body use some vitamins and keep the skin healthy. They also serve as energy stores for the body. In food, there are two types of fats: saturated and unsaturated.

Question 10

Triglyceride

Answer 10

The chemical or substrate form in which most fat exists in food as well as in the body.

Question 11

Free fatty acids

Answer 11

The by-products of the breakdown of stored or consumed fats, metabolized exclusively via the aerobic pathway, which uses oxygen to create adenosine triphosphate.

Question 12

Protein

Answer 12

Amino acids linked by peptide bonds; the building blocks of body tissues.

Question 13

Essential amino acid (EAA)

Answer 13

Amino acid that must be obtained through the diet as the body does not make it; there are nine essential amino acids.

Question 14

Nonessential amino acids

Answer 14

Amino acids that can be synthesized by the body and do not, under normal circumstances, need to be obtained in the diet.

Question 15

Negative energy balance

Answer 15

When calorie intake is lower than the number of calories expended.

Question 16

Gluconeogenesis

Answer 16

The formation of glucose from noncarbohydrate sources (proteins and fats).

Question 17

Ketogenesis

Answer 17

The formation of ketone bodies from nonfat sources, such as certain amino acids.

Question 18

Ketone bodies

Answer 18

Water-soluble molecules produced in the liver as a result of fatty acid oxidation. They can then be oxidized in the mitochondria to produce adenosine triphosphate.

Question 19

Ketosis

Answer 19

A state of carbohydrate depletion where the liver manufactures ketone bodies to meet energy demands that free fatty acid oxidation cannot support.

Question 20

Exogenous ketones

Answer 20

Isolated ketone bodies usually consumed in supplement form.

Question 21

Insulin resistance

Answer 21

The inability of the cells to respond to insulin; occurs in type 2 diabetes.

Question 22

Ketoacidosis

Answer 22

Metabolic acidosis induced by very high levels of ketone bodies such as seen in type 1 diabetes or severe insulin resistance.

Question 23

Mechanical work

Answer 23

The physical processes that move the body and keep it alive, such as muscle contraction.

Question 24

Adenosine diphosphate (ADP)

Answer 24

A high-energy compound occurring in all cells from which adenosine triphosphate is formed.

Question 25

Phosphorylation

Answer 25

The addition of a phosphate group to a molecule, such as in the transfer of a phosphate group to adenosine diphosphate to create adenosine triphosphate.

Question 26

ATP-PC System

Answer 26

An energy system that provides energy very rapidly, for approximately 10–15 seconds, via anaerobic metabolism

Question 27

Phosphorylation

Answer 27

The addition of a phosphate group to a molecule, such as in the transfer of a phosphate group to adenosine diphosphate to create adenosine triphosphate.

Question 28

ATP-PC System

Answer 28

An energy system that provides energy very rapidly, for approximately 10–15 seconds, via anaerobic metabolism.

Question 29

Anaerobic

Answer 29

Processes relating to the absence of oxygen.

Question 30

Glycolysis

Answer 30

A metabolic process that occurs in the cytosol of a cell that converts glucose into pyruvate and adenosine triphosphate. Anaerobic glycolysis refers to when this process occurs in the absence of oxygen.

Question 31

Oxidative phosphorylation

Answer 31

A series of reactions inside the mitochondria that uses oxygen to produce adenosine triphosphate.

Question 32

Aerobic

Answer 32

Processes relating to, involving, or requiring oxygen.

Question 33

Deamination

Answer 33

The breakdown of amino acids into substrates that can be used for energy metabolism.

Question 34

Mitochondria

Answer 34

The parts of the cell that use nutrients to create energy for the cell; commonly known as the powerhouses of the cell.

Question 35

Electron transport chain (ETC)

Answer 35

A series of protein complexes that transfer protons and electrons received from the citric acid cycle through a series of reactions to create adenosine triphosphate.

Question 36

Acetyl coenzyme A

Answer 36

Produced by the breakdown of carbohydrates through glycolysis and by the fatty acids through beta-oxidation and is the precursor for these substrates to the citric acid cycle.

Question 37

Beta-oxidation

Answer 37

The first step in the process to break down fats via oxidative phosphorylation.

Question 38

Macronutrients

Answer 38

Food substances required in large amounts to supply energy and include protein, carbohydrate, and fat.6

Question 39

Physical activity level (PAL)

Answer 39

The number of calories a person expends through physical activity and structured exercise.