Deck 9: Energy Metabolism

Question 1

The energy currency the body uses is

A) NAD.
B) FAD.
C) TCA.
D) ATP.

Answer 1

D

Question 2

In metabolism,glucose is degraded to CO₂ and water.The carbon dioxide is produced in

A) the red blood cells.
B) the citric acid cycle.
C) glycolysis.
D) the electron transport chain.

Answer 2

B

Question 3

When a compound is oxidized it ______ one or more electrons.

A) loses
B) gains
C) transforms
D) creates

Answer 3

A

Question 4

All the chemical and physical processes involved in maintaining life are referred to as

A) anabolism.
B) catabolism.
C) homeostasis.
D) metabolism.

Question 5

When a compound is reduced it _____ one or more electrons.

A) loses
B) gains
C) transforms
D) creates

Question 6

Nicotinamide adenine dinucleotide (NAD)

A) transports oxygen in various metabolic pathways.
B) picks up and delivers hydrogens to acceptor molecules.
C) is another form of ATP.
D) is a form of lactic acid.

Question 7

If oxygen is present,metabolism is considered to be

A) active.
B) anaerobic.
C) aerobic.
D) inactive.

Question 8

All the energy available to humans has its origins in

A) carbon dioxide and water.
B) the oxygen we breathe.
C) foods and beverages.
D) the sun's solar energy.

Question 9

How many molecules of lactate are produced from one molecule of glucose?

A) 2
B) 4
C) 6
D) 8

Question 10

Glycolysis begins with _________ and ends with __________.

A) pyruvate; water
B) pyruvate; glucose
C) glucose; pyruvate
D) pyruvate; acetyl-CoA

Question 11

Glycolysis is a process involving

A) synthesis of fatty acids
B) reactions that convert glucose to glycogen.
C) reactions that convert glucose to pyruvate.
D) reactions that convert glycogen to protein.

Question 12

Under anaerobic conditions,how many net ATP are synthesized from one glucose molecule?

A) 1 ATP.
B) 2 ATP.
C) 4 ATP.
D) 2 GTP.
E) None of these choices are correct.

Question 13

Oxidation-reduction reactions in the body are controlled by

A) light and dark cycles.
B) enzymes.
C) fluid balance.
D) protein consumption.

Question 14

In the absence of oxygen,______ respiration will occur.

A) active
B) anaerobic
C) aerobic
D) inactive

Question 15

Red blood cells undergo anaerobic metabolism,which means that they produce

A) plasma.
B) iron.
C) lactate.
D) clots.

Question 16

Photosynthesis occurs in plants and uses energy from the sun to

A) produce organic compounds from carbon, hydrogen, and oxygen.
B) produce energy-yielding compounds.
C) heat the environment.
D) make plants turn yellow.

Question 17

The citric acid cycle is also known as the

A) urea cycle.
B) Krebs cycle.
C) menstrual cycle.
D) aerobic pathway.

Question 18

When muscle tissue is exercising under anaerobic conditions,the production of ______ is important because it ensures a continuous supply of NAD⁺.

A) glucose-6-phosphate
B) pyruvate
C) lactate
D) glycogen

Question 19

The conversion of pyruvate to acetyl-CoA

A) requires the addition of CO₂.
B) occurs in the mitochondria of the cell and is irreversible.
C) occurs in the nucleus of the cell.
D) is needed for red blood cell production.

Question 20

Flavin adenine dinucleotide is a coenzyme form of the vitamin

A) pantothenic acid.
B) niacin.
C) thiamin.
D) riboflavin.

Question 21

Carnitine

A) is a dietary essential, especially for athletes.
B) shuttles NADH across the mitochondrial membrane.
C) shuttles oxaloacetate from the mitochondria to the cytosol.
D) shuttles fatty acids from the cytosol into the mitochondria.

Question 22

In most cases the starting material for gluconeogenesis is

A) oxaloacetate.
B) phosphoenolpyruvate.
C) carnitine.
D) All of these choices are correct.

Question 23

Ketones are produced from:

A) cholesterol.
B) hormones.
C) amino acids.
D) acetyl-CoA.

Question 24

Amino acids (or parts of their carbon skeletons)that can be converted to pyruvate or enter the citric acid cycle directly are called

A) glucogenic amino acids.
B) ketogenic amino acids.
C) essential amino acids.
D) non-essential amino acids.

Question 25

Cytochromes

A) are produced by photosynthesis.
B) transport electrons in the electron transport chain.
C) appear in the citric acid cycle.
D) are responsible for beta-oxidation of fatty acids.

Question 26

After a person has fasted for about a week,the brain adapts to using _______ for some of its fuel needs.

A) glycerol
B) ketones
C) fatty acids
D) amino acids

Question 27

When there is excess glucose and amino acids in the liver,and no more ATP needs to be synthesized,these energy-rich nutrients are converted to

A) triglycerides.
B) pyruvate.
C) NAD⁺.
D) FAD.

Question 28

Gluconeogenesis is the process whereby the body

A) converts glucose to its storage form.
B) retrieves stored glucose from the liver.
C) lowers the glucose level of the blood.
D) produces glucose from amino acid and glycerol molecules.

Question 29

Amino acids that become acetyl-CoA as a result of deamination are designated ketogenic amino acids because

A) they can become parts of the glucose molecule.
B) they cannot become part of the glucose molecule.
C) they interfere with metabolism of fatty acids.
D) all amino acids are interchangeable through the citric acid cycle.

Question 30

Which of the following pathways is the major way in which alcohol is metabolized?

A) pyruvate dehydrogenase pathway
B) ethanol dehydrogenase pathway
C) lactate dehydrogenase pathway
D) alcohol dehydrogenase pathway

Question 31

The major end products of the electron transport chain are

A) water, carbon dioxide and ATP.
B) glucose and amino acids.
C) dietary fiber and ammonia.
D) carbon, nitrogen and hydrogen.

Question 32

The synthesis of fatty acids occurs in the _________ of the cell and the breakdown of fatty acids occurs in the _______ of the cell.

A) mitochondria; cytosol
B) nucleus; cytosol
C) cytosol; mitochondria
D) cytosol; lysosome

Question 33

Before protein becomes an energy source,the _________ must be removed from the molecule.

A) COOH
B) CH₃
C) NH₂
D) CO₂

Question 34

In fatty acid synthesis,the "starting" molecule is

A) glycerol.
B) acetyl-CoA.
C) ATP.
D) pyruvate.

Question 35

The process of simply losing an amine group from amino acids is called:

A) deamination
B) desaturation
C) beta oxidation
D) denaturation

Question 36

During the end reaction of the electron transport chain,oxygen becomes

A) reduced to water (H₂O).
B) oxidized to carbon dioxide
C) NADH.
D) FADH₂.

Question 37

In which compartment of the cell do Krebs cycle and fatty acid oxidation take place?

A) cell membrane.
B) mitochondria.
C) nucleus.
D) cytosol.

Question 38

Ketosis increases with

A) fasting.
B) a low-carbohydrate diet.
C) uncontrolled type 1 diabetes mellitus.
D) All of these choices are correct.

Question 39

The common pathway for the oxidation of glucose and fatty acids is

A) glycolysis.
B) the Cori cycle.
C) the citric acid cycle.
D) ketosis.

Question 40

When the carbon skeleton of an amino acid is oxidized for energy,the amino group is removed and sent to the liver to produce

A) ammonia.
B) protein.
C) urea.
D) albumin.

Question 41

Beta-oxidation is the process by which

A) fatty acids break apart to form acetyl-CoA.
B) glucose breaks apart to form pyruvate.
C) amino groups move from a donor to an acceptor.
D) NADH + H⁺ and FADH₂ are converted to NAD⁺ and FAD, donating electrons and hydrogen ions to oxygen.
E) energy derived from NADH + H⁺ and FADH₂ is used to generate ATP.

Question 42

In the metabolism of amino acids for energy,the amine group is

A) stored in the liver.
B) converted to glucose.
C) excreted as urea.
D) burned for energy.

Question 43

Anabolic metabolism refers to pathways that build larger,more complex compounds.

Question 44

Metabolism is regulated by

A) hormones such as insulin.
B) the presence and activity of enzymes.
C) ATP levels in the individual cells.
D) All of these choices are correct.

Question 45

Oxidative phosphorylation is the process by which

A) fatty acids break apart to form acetyl-CoA.
B) glucose breaks apart to form pyruvate.
C) amino groups move from a donor to an acceptor.
D) NADH + H⁺ and FADH₂ are converted to NAD⁺ and FAD, donating electrons and hydrogen ions to oxygen.
E) energy derived from NADH + H⁺ and FADH₂ is used to generate ATP.

Question 46

Gluconeogenesis takes place in both the cytosol and the mitochondria.

Question 47

Transamination is the process by which

A) fatty acids break apart to form acetyl-CoA.
B) glucose breaks apart to form pyruvate.
C) amino groups are transferred from a donor to an acceptor.
D) NADH + H⁺ and FADH₂ are converted to NAD⁺ and FAD, donating electrons and hydrogen ions to oxygen.
E) energy derived from NADH + H⁺ and FADH₂ is used to generate ATP.

Question 48

After a period of prolonged fasting (starving),the brain changes its fuel requirements

A) and uses amino acids directly.
B) and starts to use glycerol as the primary source of energy.
C) and starts to use ketones and spares protein.
D) and glycogen becomes the primary source of energy.

Question 49

When excessive amounts of alcohol are consumed,which system oxidizes the excess alcohol?

A) beta oxidizing system
B) mitochondrial oxidizing system
C) alcohol oxidizing system
D) microsomal ethanol oxidizing system

Question 50

Where does alcohol metabolism predominantly occur in the body?

A) intestines
B) liver
C) kidney
D) lungs

Question 51

Fasting or starvation accelerates

A) gluconeogenesis.
B) ketone production.
C) body protein breakdown.
D) body fat breakdown.
E) All of these choices are correct.

Question 52

Beta oxidation takes place in the mitochondria.

Question 53

Typical fatty acids cannot be converted to glucose because

A) they lack sufficient energy.
B) they enter the citric acid cycle at acetyl-CoA and can never reform pyruvate.
C) they can only be synthesized from amino acid skeletons, not fatty acid skeletons.
D) they enter the citric acid cycle as propionyl-CoA.

Question 54

The kidney is the major organ that regulates metabolism.

Question 55

Electron transport is the process by which

A) fatty acids break apart to form acetyl-CoA.
B) glucose breaks apart to form pyruvate.
C) amino groups move from a donor to an acceptor.
D) NADH + H⁺ and FADH₂ are converted to NAD⁺ and FAD, donating electrons and hydrogen ions to oxygen.
E) energy derived from NADH + H⁺ and FADH₂ is used to generate ATP.

Question 56

Which of the following energy-yielding nutrients can be converted to glucose?

A) carbohydrates
B) lipids
C) proteins
D) carbohydrates and proteins

Question 57

In the body,excess amino acids are

A) burned as fuel or stored as fat.
B) stored by the body in the form that they were consumed.
C) of no concern to health status.
D) directly converted into lean muscle mass.

Question 58

Catabolic metabolism refers to pathways that break down compounds to smaller,simpler units.

Question 59

The conversion of pyruvate to acetyl-CoA is irreversible.

Question 60

Glycolysis is the process by which

A) fatty acids break apart to form acetyl-CoA.
B) glucose breaks apart to form pyruvate.
C) amino groups move from a donor to an acceptor.
D) NADH + H⁺ and FADH₂ are converted to NAD⁺ and FAD, donating electrons and hydrogen ions to oxygen.
E) energy derived from NADH + H⁺ and FADH₂ is used to generate ATP.

Question 61

Ketone bodies are products of incomplete oxidation of fatty acids.

Question 62

Explain why individuals with undiagnosed diabetes lose weight.

Question 63

Name two characteristics of inborn errors of metabolism.

Question 64

Differentiate between aerobic and anaerobic metabolism.How does this apply to physical activity?

Question 65

Explain what happens to ketone levels in the body after prolonged starvation.

Question 66

Explain why some people think that consuming carnitine pills will help them lose weight.

Question 67

The conversion of pyruvate to acetyl-CoA is reversible.

Question 68

Diabetic ketoacidosis is a result of a lack of insulin.

Question 69

High amounts of ketones in the blood show that the body is using protein as a fuel source.

Question 70

During an overnight fast,the primary fuel for the brain and central nervous system is amino acids.

Question 71

Explain the meaning of the phrase: "fat burns in the flame of carbohydrates."

Question 72

Why can't typical fatty acids be used as substrates for gluconeogenesis?

Question 73

The electron transport chain takes place in the cytosol.

Question 74

Why is the mitochondrion called the powerhouse of the cell?

Question 75

Name 3 basic metabolic processes in the body.

Question 76

Describe one inborn error of metabolism,discussing the metabolic process it affects,the consequences of the disease,and its treatment.

Question 77

Why do fats yield more energy per gram than proteins or carbohydrates?

Question 78

Using metabolic terms,explain how the MEOS system is different from the alcohol dehydrogenase pathway for metabolism of alcohol.

Question 79

The body can make glucose from fatty acids.