Deck 25: Metabolism, Nutrition, and Energetics

Question 1

All of the following occur during glycolysis, except

A) a molecule of glucose is converted into two molecules of pyruvic acid.
B) four molecules of ATP are produced.
C) two molecules of ATP are consumed.
D) hydrogen atoms are removed from organic molecules.
E) a molecule of carbon dioxide is produced.

Answer 1

E

Question 2

The major steps in oxidative phosphorylation include all of the following except

A) removal of hydrogen atoms from a substrate molecule by coenzymes.
B) ionization of hydrogen atoms.
C) decreasing the energy level of electrons passing through the electron transport chain.
D) the breaking of carbon-carbon covalent bonds.
E) the acceptance of electrons by oxygen atoms.

Answer 2

D

Question 3

Intermediary molecules that accept electrons and transfer them to another molecule are called

A) nutrients.
B) organics.
C) ketones.
D) metabolites.
E) coenzymes.

Answer 3

E

Question 4

The ________ of the mitochondrion contains large-diameter pores that are permeable to ions and small organic molecules such as pyruvic acid.

A) inner membrane
B) plasma membrane
C) outer membrane
D) matrix
E) cristae

Question 5

The strategy of eating starchy foods for several days before an athletic event is known as

A) carbohydrate craving.
B) the Atkins diet.
C) carbohydrate loading.
D) glycolysis reaction.
E) overeating.

Question 6

The citric acid cycle

A) begins with the formation of a molecule of citric acid.
B) directly produces most of the ATP from the catabolism of glucose.
C) consumes two moles of carbon dioxide.
D) contains enzymes called cytochromes.
E) forms acetyl-CoA from glucose-6-phosphate.

Question 7

In glycolysis, each molecule of glucose that is catabolized gives a net yield of how many molecules of ATP?

A) 2
B) 4
C) 30
D) 36
E) 38

Question 8

The study of the flow of energy and its transformations is called

A) energetics.
B) glycolysis.
C) cellular respiration.
D) thermodynamics.
E) metabolism.

Question 9

The first steps of catabolism generally take place in the

A) mitochondria.
B) plasma membrane.
C) nucleus.
D) endoplasmic reticulum.
E) cytosol.

Question 10

Reactions within ________ provide most of the energy needed by a typical cell.

A) cytoplasm
B) the plasma membrane
C) the mitochondria
D) the endoplasmic reticulum
E) nucleus

Question 11

The function of the citric acid cycle is to

A) remove hydrogen atoms from organic molecules and transfer them to coenzymes.
B) transfer the acetyl group gained from glycolysis to molecules of pyruvate.
C) hydrolyze glucose in the presence of oxygen to obtain two pyruvate molecules.
D) produce carbon dioxide to balance the oxygen requirement for cellular respiration.
E) produce water.

Question 12

Although other nutrients can feed into the citric acid cycle, ________ yields energy the quickest.

A) glycogen
B) glucose
C) protein
D) fat
E) an amino acid

Question 13

What is the role of NADH in metabolism?

A) convert pyruvic acid into acetyl-coA
B) produce bicarbonate ions for a pH buffer
C) transport hydrogen atoms to coenzymes
D) produce carbon dioxide
E) phosphorylate ADP into ATP

Question 14

The chemical equation that correctly summarizes the overall reaction in oxidative phosphorylation is
A) H2 + O2 ? H2O + O.

A) H2 + O2 ? H2O.
B) 2 H2 + O2 ? 2 H2O.
B) P + 3 O ? PO3.
C) 3 H? + 2O? ? 3 H?O + 2 O.

Question 15

The carbon dioxide of respiration is formed during

A) glycolysis.
B) the citric acid cycle.
C) electron transport.
D) the formation of pyruvic acid.
E) the formation of water.

Question 16

All the available nutrient molecules distributed in the blood form a

A) nutrient storehouse.
B) nutrient reserve.
C) nutrient pool.
D) energy reserve.
E) organic storehouse.

Question 17

In order for glycolysis to proceed, which of the following need not be present?

A) glucose
B) acetyl-CoA
C) ATP
D) NAD
E) ADP

Question 18

When NAD+ is ________ it becomes NADH. When NADH is ________ it becomes NAD+.

A) phosphorylated; deaminated
B) reduced; oxidized
C) made; recycled
D) phosphorylated; dephosphorylated
E) oxidized; reduced

Question 19

In the ETS, ________ accepts electrons from one molecule and transfers them to another.

A) a hydrogen ion
B) a coenzyme
C) the acetyl group
D) ADP
E) NAD

Question 20

The sum of all of the biochemical processes going on within the human body at any given time is called

A) glycolysis.
B) oxidative phosphorylation.
C) catabolism.
D) anabolism.
E) metabolism.

Question 21

Cyanide gas is lethal because it

A) inhibits the kinase that phosphorylates ATP.
B) inhibits the ATP synthase.
C) blocks substrate-level phosphorylation.
D) blocks the final electron acceptor in the ETS.
E) binds NAD preventing it from being reduced.

Question 22

The formation of GTP from GDP in the citric acid cycle is an example of

A) substrate-level phosphorylation.
B) oxidative phosphorylation.
C) decarboxylation.
D) cellular respiration.
E) aerobic metabolism.

Question 23

The two most important coenzymes for glycolysis and the citric acid cycle are

A) ATP and ADP.
B) FAD and FMN.
C) NAD and ATP.
D) NAD and FAD.
E) ATP and GTP.

Question 24

In the citric acid cycle, a 2 carbon molecule and a 4 carbon molecule combine to produce

A) fructose-1, 6-bisphosphate.
B) carbon dioxide.
C) pyruvic acid.
D) NADH.
E) citric acid.

Question 25

The end products of glycolysis are

A) ATP, water, and carbon dioxide.
B) ATP, NADH, and pyruvic acid.
C) ADP and ATP.
D) pyruvic acid and citric acid.
E) NADH and FADH2.

Question 26

The main purpose of the citric acid cycle is to

A) produce Acetyl CoA so that the citric acid cycle can continue.
B) produce proteins for energy storage.
C) phosphorylate glucose molecules.
D) supply hydrogen atoms to the Electron Transport System.
E) produce citric acid to make vitamin C in the mitochondria.

Question 27

The process of glycogen formation is known as

A) glycolysis.
B) gluconeogenesis.
C) cellular respiration.
D) glycemia.
E) glycogenesis.

Question 28

During the citric acid cycle, both NAD and FAD ________ a hydrogen atom and become ________.

A) lose; oxidized
B) gain; oxidized
C) lose; reduced
D) gain; reduced
E) gain; ATP

Question 29

Most of the ATP from metabolism is produced in the

A) citric acid cycle.
B) electron transport system.
C) cytosol.
D) mitochondrial matrix.
E) glycolysis.

Question 30

Fatty acids and many amino acids cannot be used for ________ because their catabolic pathways produce acetyl-CoA.

A) glycolysis
B) gluconeogenesis
C) cellular respiration
D) glycemia
E) glycogenesis

Question 31

In oxidative phosphorylation, energy for the synthesis of ATP is directly obtained from the

A) splitting of oxygen molecules.
B) breaking of the covalent bonds in glucose.
C) movement of hydrogen ions through channels in the inner mitochondrial membrane.
D) combination of two atoms of hydrogen and one atom of oxygen to form water.
E) oxidation of acetyl-CoA.

Question 32

The electron transport system doesn't produce ATP directly instead it uses the hydrogen ion gradient todrive

A) substrate-level phosphorylation.
B) chemiosmosis.
C) anaerobic metabolism.
D) decarboxylation.
E) deamination.

Question 33

Carbon and oxygen atoms are removed as carbon dioxide in a process called

A) anabolism.
B) decarboxylation.
C) deamination.
D) oxidative phosphorylation.
E) substrate-level phosphorylation.

Question 34

The end products of aerobic respiration are

A) carbon dioxide, water, and ATP.
B) pyruvic acid and carbon dioxide.
C) carbon dioxide and alcohol.
D) oxygen and water.
E) NADH and FADH2.

Question 35

Oxygen is an important molecule in which of the following?

A) citric acid cycle and ETS
B) glycolysis, citric acid cycle, and ETS
C) citric acid cycle only
D) glycolysis only
E) ETS only

Question 36

The citric acid cycle occurs in the

A) cytosol.
B) golgi apparatus.
C) mitochondrial intermembrane space.
D) mitochondrial matrix.
E) ribosome.

Question 37

How many net ATP molecules are produced by the complete metabolism (all pathways) of one glucose molecule?

A) 2-4 ATP
B) 6 ATP
C) 30-32 ATP
D) 100-120 ATP
E) 150 ATP

Question 38

The process of synthesizing glucose from noncarbohydrates is called

A) glycolysis.
B) gluconeogenesis.
C) cellular respiration.
D) glycemia.
E) glycogenesis.

Question 39

Figure 25-1 The Citric Acid Cycle
Use Figure 25-1 to answer the following questions:
What is the molecule labeled "1"?

A) phosphoglyceric acid
B) citric acid
C) pyruvate
D) NADH
E) FADH2

Question 40

The citric acid cycle is an aerobic process because

A) ADP is phosphorylated.
B) FADH2 is produced.
C) citric acid molecules have oxygen atoms.
D) oxygen is needed to remove carbon atoms as carbon dioxide.
E) NAH+ is converted into NADH.

Question 41

Fatty acids that are necessary for proper health but cannot be synthesized by the body are called ________fatty acids.

A) oxidative
B) metabolic
C) essential
D) vital
E) non-metabolic

Question 42

Figure 25-1 The Citric Acid Cycle
Use Figure 25-1 to answer the following questions:
What is the molecule labeled "2"?

A) hydrogen atoms
B) citric acid
C) NADH
D) carbon dioxide
E) FADH2

Question 43

________ carry excess cholesterol from peripheral tissues to the liver.

A) Very-low-density lipoproteins (VLDLs)
B) Low-density lipoproteins (LDLs)
C) Micelles
D) High-density lipoproteins (HDLs)
E) Very-high-density lipoproteins (VHDLs)

Question 44

Lipoproteins that are formed within the intestinal epithelium to transfer dietary fats into circulationarecalled

A) chylomicrons.
B) very-low-density lipoproteins.
C) micelles.
D) low-density lipoproteins.
E) high-density lipoproteins.

Question 45

Lipoproteins that are primarily sent to skeletal muscles and adipose tissues are called

A) chylomicrons.
B) very-low-density lipoproteins.
C) micelles.
D) low-density lipoproteins.
E) high-density lipoproteins.

Question 46

Figure 25-1 The Citric Acid Cycle
Use Figure 25-1 to answer the following questions:
What is the molecule labeled "3"?

A) ADP
B) carbon dioxide
C) NADH
D) hydrogen atoms
E) pyruvate

Question 47

During lipolysis,

A) triglycerides are converted into molecules of acetyl-CoA.
B) triglycerides are broken down into glycerol and fatty acids.
C) lipids are converted into glucose molecules.
D) lipids are formed from excess carbohydrates.
E) lipids are metabolized to yield ATP.

Question 48

Figure 25-1 The Citric Acid Cycle
Use Figure 25-1 to answer the following questions:
What is the molecule labeled "7"?

A) hydrogen atoms
B) citric acid
C) 4 carbon molecule
D) NADH
E) FADH2

Question 49

Lipoproteins are water-soluble because of a superficial coating of

A) cholesterol.
B) bile salts.
C) phospholipids and proteins.
D) triglycerides.
E) glycerol.

Question 50

All of the following are true of beta-oxidation except that

A) it occurs in the mitochondria.
B) fatty acids break down into two-carbon fragments.
C) lipids are converted into glycogen molecules.
D) it requires coenzyme A, NAD, and FAD.
E) it yields large amounts of ATP.

Question 51

The complete catabolism of fatty acids is through the process called

A) lipogenesis.
B) glycolysis.
C) beta-oxidation.
D) glycogenolysis.
E) adipogenesis.

Question 52

Figure 25-1 The Citric Acid Cycle
Use Figure 25-1 to answer the following questions:
What is the substance labeled "4"?

A) hydrogen atoms
B) citric acid
C) 4 carbon molecule
D) NADH
E) FADH2

Question 53

Lipogenesis generally begins with

A) glucose.
B) amino acids.
C) fatty acids.
D) acetyl-CoA.
E) succinyl-CoA.

Question 54

Lipogenesis is common for organic molecules because the intermediate ________ is formed in most nutrientmetabolic processes.

A) pyruvate
B) acetyl-CoA
C) glycerol
D) glucose
E) lipoprotein

Question 55

The lipoproteins that carry absorbed lipids from the intestinal tract to the bloodstream are

A) HDLs.
B) VLDLs.
C) LDLs.
D) chylomicrons.
E) coenzymes.

Question 56

________ are the largest lipoproteins, ranging in diameter up to 0.5 µm.

A) Very-low-density lipoproteins (VLDLs)
B) Low-density lipoproteins (LDLs)
C) Micelles
D) High-density lipoproteins (HDLs)
E) Chylomicrons

Question 57

Lipids

A) deliver somewhat less energy than an equivalent mass of glucose.
B) are difficult to store since they are not water soluble.
C) yield quick bursts of energy.
D) provide energy for cells with modest energy demands.
E) are the primary nutrient metabolized in cells.

Question 58

Lipoproteins that carry mostly cholesterol to peripheral tissues are called

A) chylomicrons.
B) very-low-density lipoproteins.
C) micelles.
D) low-density lipoproteins.
E) high-density lipoproteins.

Question 59

Linoleic acid and linolenic acid are examples of

A) transport proteins.
B) lipoproteins.
C) essential fatty acids.
D) essential amino acids.
E) vitamins.

Question 60

In order to determine the LDL level in a patient's blood, it is necessary to measure

A) total cholesterol level.
B) HDL level.
C) triglyceride level.
D) triglyceride and monoglyceride levels.
E) total cholesterol level, HDL level, and triglyceride level.

Question 61

During the absorptive state,

A) the liver forms glycogen.
B) adipocytes release fatty acids to the circulation.
C) skeletal muscle breaks down glycogen.
D) insulin levels are low.
E) skeletal muscle fibers release glucose.

Question 62

The removal of amino group from a protein to prepare it to enter the citric acid cycle is termed

A) transamination.
B) deamination.
C) decarboxylation.
D) amination.
E) beta-oxidation.

Question 63

During the postabsorptive state, ________ stimulate(s) lipid catabolism.

A) glucocorticoids
B) androgens
C) insulin
D) glucagon
E) gastrin

Question 64

Compounds that cells can use to make glucose include all of the following, except

A) acetyl-CoA.
B) glycerol.
C) some amino acids.
D) lactate.
E) pyruvate.

Question 65

Frank has diabetes mellitus and his blood pH has dropped. What is the most likely cause of his acidosis?

A) a build up of urea
B) excess ammonia production
C) lipoprotein metabolism
D) excess ketone formation
E) increased glycolysis

Question 66

On a tour of African countries, Mark contracts a bad case of traveler's diarrhea. Because he can't eat verymuch, his body starts to use energy sources other than carbohydrates. This would result in all of the following, except

A) increased levels of urea in the blood.
B) ketosis and a decreased blood pH.
C) increased gluconeogenesis in the liver.
D) lipid metabolism.
E) glycogenesis.

Question 67

Protein malnourishment may occur if the diet is deficient in

A) essential amino acids.
B) nonessential amino acids.
C) urea.
D) ammonia.
E) keto acids.

Question 68

In transamination, the amino group of an amino acid is

A) converted to ammonia.
B) converted to urea.
C) transferred to a keto acid.
D) absorbed by water.
E) transferred to acetyl-CoA.

Question 69

Metabolism of amino acids in the citric acid cycle yields

A) more energy than lipid metabolism.
B) more energy than carbohydrate metabolism.
C) approximately the same energy as lipid metabolism.
D) approximately the same energy as carbohydrate metabolism.
E) more energy than lipid and carbohydrate metabolism combined.

Question 70

A high uric acid level (above 7.4 mg/dl) can lead to the painful condition known as

A) gout.
B) rheumatoid arthritis.
C) anorexia nervosa.
D) lupus.
E) ketosis.

Question 71

Removal of the amino group from amino acids in the first step of their catabolism requires a coenzyme derived from vitamin

A) A.
B) C.
C) B12.
D) B6.
E) B9.

Question 72

All of the following complement the actions of glucocorticoids in the postabsorptive state except

A) insulin.
B) growth hormone.
C) glucagon.
D) epinephrine.

Question 73

During starvation,

A) carbohydrate utilization increases.
B) gluconeogenesis ceases.
C) there is a decline in circulating ketone bodies.
D) muscle proteins are used as an energy source.
E) carbohydrate reserves maintained by metabolizing inorganic compounds.

Question 74

Catabolism of protein is not a practical source of quick energy because of all of the following except that

A) proteins are more difficult to break apart than lipids or carbohydrates.
B) the energy yield from protein is less than the yield from lipids.
C) one of the by-products of protein catabolism is ammonia.
D) most individuals have little protein to spare before harming vital organs.
E) extensive catabolism of protein threatens homeostasis.

Question 75

Following a meal, the absorptive state lasts approximately

A) 30 minutes.
B) 2 hours.
C) 4 hours.
D) 8 hours.
E) 12 hours.

Question 76

When the body is relying on internal energy reserves to continue meeting its energy demands, it is in the ________ state.

A) postabsorptive
B) absorptive
C) starvation
D) deprivation
E) preabsorptive

Question 77

Nitrogen compounds of the body include all of the following except

A) amino acids.
B) oxaloacetate.
C) creatine.
D) porphyrin.
E) purines.

Question 78

The conversion of ammonia into a less toxic substance produces

A) ketone bodies.
B) urea.
C) nitrate.
D) acetyl-CoA.
E) water.

Question 79

All of the following occur during the postabsorptive state except that

A) glycogenolysis occurs in the liver.
B) levels of blood glucose are elevated above normal.
C) ketone bodies may be formed.
D) fat mobilization occurs.
E) gluconeogenesis occurs in the liver.

Question 80

Urea is formed in the

A) liver.
B) stomach.
C) kidneys.
D) small intestine.
E) large intestine.