Chapter 8

Question 1

Bioenergetics

Answer 1

The study of energy in the human body

Question 2

Metabolism

Answer 2

The chemical reactions that occur in the body to maintain itself

Question 3

Exercise metabolism

Answer 3

The examination of bioenergetics as it relates to the unique physiologic changes and demands placed on the body during exercise

Question 4

Identify two metabolic changes that occur during exercise

Answer 4

Increased energy demand
Increased disposal of metabolic waste products

Question 5

Three main sources of energy for the human body

Answer 5

Carbohydrates, fat, proteins

Question 6

The energy currency of the body

Answer 6

ATP

Question 7

First law of thermodynamics

Answer 7

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

Question 8

Macronutrients

Answer 8

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

Question 9

The body is a *** system

Answer 9

closed

Question 10

All of the energy someone consumes is either used or stored within the body

Answer 10

True

Question 11

All life on earth is *** based

Answer 11

carbon

Question 12

*** is the element that mainly contributes to the physical mass of a living object

Answer 12

Carbon

Question 13

Energy starts as **, is then converted to various forms within the body during metabolism, and is finally released back to the environment as ** during exhalation

Answer 13

Food
CO2

Question 14

Substrates

Answer 14

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

Question 15

A small selection of substrates that cannot be created internally and must be consumed in the diet are ***

Answer 15

Essential

Question 16

Glucose makes a relatively small contribution to overall energy production during rest or low-intensity exercise.

Answer 16

True

Question 17

The brain always requires glucose to function, but *** are what primarily fuel the body when it is not active

Answer 17

Fats

Question 18

Ventilatory threshold 1

Answer 18

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

Question 19

Ventilatory threshold 2

Answer 19

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

Question 20

Fats

Answer 20

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.

Question 21

Two types of fat in food

Answer 21

saturated and unsaturated

Question 22

Triglyceride

Answer 22

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

Question 23

Free fatty acids

Answer 23

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

Question 24

Any time an individual is exercising at an intensity below VT1, *** are the primary fuel source.

Answer 24

Free fatty acids

Question 25

1 lb of body fat is ~ *** calories of stored energy

Answer 25

3500

Question 26

Proteins

Answer 26

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

Question 27

Essential amino acid

Answer 27

Amino acid that must be obtained through the diet as the body does not make it

Question 28

How many amino acids are essential?

Answer 28

Nine

Question 29

Humans use *** amino acids to assemble body proteins

Answer 29

20

Question 30

Nonessential amino acids

Answer 30

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

Question 31

Negative energy balance

Answer 31

When calorie intake is lower than the number of calories expended

Question 32

Amino acid building blocks are used to synthesize human bodily proteins that ***

Answer 32

build up muscle and repair cellular machinery

Question 33

Amino acids from dietary protein can also supply energy for ATP production if carbohydrate and fat sources are low

Answer 33

True

Question 34

Before amino acids can be used to make ATP, they are further broken down and then recombined into either glucose through a process called *** or ketone bodies through a process called ***

Answer 34

Gluconeogenesis Ketogenesis

Question 35

Ketogenesis

Answer 35

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

Question 36

Gluconeogenesis

Answer 36

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

Question 37

Ketone bodies

Answer 37

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 38

Ketosis

Answer 38

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

Question 39

The human body does not have the ability to store ***, so they are only used acutely to produce energy and are not stored for later like glycogen

Answer 39

Ketones

Question 40

List four factors that can increase ketones in the body

Answer 40

Caloric restriction Low carbohydrate diet Exogenous ketones Low insulin release or high insulin resistance

Question 41

Nutritional ketosis is defined as *** mmol of ketones/L of blood

Answer 41

0.5-1.5 mmol of ketones/L of blood

Question 42

Ketoacidosis

Answer 42

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

Question 43

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

Answer 43

Mechanical work