Deck 7: Energy Metabolism

Question 1

Which of the following CANNOT be formed from acetyl CoA molecules?

A)Glucose
B)Cholesterol
C)Stearic acid
D)Carbon dioxide

Answer 1

A

Question 2

When a balanced diet is consumed,approximately what percentage of the body's energy expenditure is furnished by amino acids?

A)1 to 5
B)10 to 15
C)25 to 35
D)50 to 65

Answer 2

B

Question 3

Which of the following reactions is an example of an anabolic reaction?

A)Pyruvate synthesis from glucose
B)Acetyl CoA synthesis from cholesterol
C)Carbon dioxide synthesis from citric acid
D)Cholesterol synthesis from acetyl CoA molecules

Answer 3

D

Question 4

The site of lipid synthesis in the cell is the

A)nucleus.
B)Golgi bodies.
C)mitochondria.
D)smooth endoplasmic reticulum.

Question 5

Which of the following metabolic reactions occurs when a cell uses energy?

A)ATP gains a phosphate group and becomes ADP
B)ADP gains a phosphate group and becomes ATP
C)ATP releases a phosphate group and becomes ADP
D)ADP releases a phosphate group and becomes ATP

Question 6

Which of the following defines a coenzyme?

A)A unit consisting of an enzyme bound to reactants plus ATP
B)An organic molecule required for the functioning of an enzyme
C)The small,active part of an enzyme that binds to the organic reactants
D)An inactive enzyme that becomes functional upon contact with specific cofactors

Question 7

In photosynthesis,the plant uses energy from the sun,plus water and carbon dioxide,to synthesize

A)carbohydrates only.
B)fats and carbohydrates only.
C)protein and carbohydrates only.
D)fats,proteins,and carbohydrates.

Question 8

Which of the following is NOT a basic unit derived from food?

A)Glycerol
B)Starches
C)Fatty acids
D)Amino acids

Question 9

What is the major energy carrier molecule in most cells?

A)ATP
B)Glucose
C)Pyruvate
D)A kcalorie

Question 10

A feature of catabolic reactions is that they

A)involve release of energy.
B)occur only in mitochondria.
C)involve consumption of energy.
D)occur only during loss of body weight.

Question 11

The hydrolysis of ATP that often occurs simultaneously with the synthesis of many compounds is an example of

A)coupled reactions.
B)tandem cleavages.
C)metabolic couplings.
D)high-energy processes.

Question 12

What is the approximate percent efficiency of conversion of food energy to ATP energy in the body?

A)20
B)50
C)80
D)99

Question 13

In the adult body,food energy not stored as fat or glycogen is lost as

A)heat.
B)photons.
C)carbon dioxide.
D)electromagnetic radiation.

Question 14

Which of the following is an example of a catabolic reaction?

A)Glucose formation from glycerol
B)Pyruvate formation from glucose
C)Albumin formation from amino acids
D)Palmitic acid formation from acetate

Question 15

Which of the following CANNOT be formed from pyruvate in human beings?

A)Glucose
B)Fructose
C)Lactic acid
D)Linoleic acid

Question 16

What term is specific to reactions in which simple compounds are combined into more complex molecules?

A)Anabolic
B)Catabolic
C)Ergogenic
D)Gluconeogenic

Question 17

Which of the following is NOT among the functions of the liver?

A)Synthesis of urea
B)Synthesis of glycogen
C)Production of red blood cells
D)Conversion of fructose to fatty acids

Question 18

Which of the following describes the sum of all chemical reactions that go on in living cells?

A)Digestion
B)Metabolism
C)Absorption
D)Catabolism

Question 19

A typical cell contains "powerhouses," which is another name for the

A)DNA.
B)ribosomes.
C)mitochondria.
D)electron transport chains.

Question 20

The formation of glycogen by the liver cell is an example of

A)oxidation.
B)glycolysis.
C)anabolism.
D)catabolism.

Question 21

Production of excessive amounts of acetyl CoA molecules leads to the synthesis of

A)fatty acids only.
B)fatty acids and glucose only.
C)fatty acids and fructose only.
D)fatty acids,glucose,and amino acids.

Question 22

What is the first product of fatty acid catabolism?

A)Glycerol
B)Pyruvate
C)Acetyl CoA
D)Triglycerides

Question 23

Fatty acid oxidation results in the direct production of

A)ketones.
B)fructose.
C)pyruvate.
D)acetyl CoA.

Question 24

Which of the following is NOT a possible fate of metabolized glucose?

A)Urea
B)Acetyl CoA
C)Amino acids
D)Muscle glycogen

Question 25

Which of the following is a possible metabolic reaction in the cell?

A)Pyruvate to urea
B)Lactate to pyruvate
C)Acetyl CoA to pyruvate
D)Carbon dioxide to glycerol

Question 26

Which of the following nutrients can be made from compounds composed of 2-carbon skeletons?

A)Glucose
B)Fructose
C)Glycogen
D)Fatty acids

Question 27

In a triglyceride that contains 54 carbon atoms,how many can become part of glucose?

A)3
B)9
C)54
D)108

Question 28

An aerobic reaction is one that requires

A)alcohol.
B)oxygen.
C)nitrogen.
D)ammonia.

Question 29

Which of the following is NOT a 3-carbon compound?

A)Lactate
B)Glycerol
C)Pyruvate
D)Acetyl CoA

Question 30

Which of the following is a feature of aerobic metabolism?

A)Little or no oxygen is consumed
B)Lactic acid is a major byproduct
C)Energy is produced more slowly than in anaerobic metabolism
D)Pyruvate is converted to glucose by reverse glycolysis to yield a net of 2 ATPs

Question 31

The series of reactions involving the conversion of glucose to pyruvate is known as

A)pyrolysis.
B)glycolysis.
C)beta-oxidation.
D)coupled reaction.

Question 32

Which of the following outlines the overall sequence of events in the complete oxidation of glucose?

A)Cori cycle,TCA cycle,glycolysis
B)Glycolysis,TCA cycle,electron transport chain
C)Electron transport chain,TCA cycle,Cori cycle
D)TCA cycle,electron transport chain,glycolysis

Question 33

The Cori cycle involves the interconversion of

A)lactate and glucose.
B)glucose and amino acids.
C)pyruvate and citric acids.
D)fatty acids and acetyl CoA.

Question 34

Which of the following is a characteristic of lactate production by muscle cells?

A)It occurs only during intense exercise
B)When rapid it causes muscle fatigue
C)The lactate produced may eventually be used by the liver for glucose production d,It lowers pH of the muscle cell,thereby lowering muscle performance

Question 35

When a person is performing intense physical exercise and begins to feel fatigue and a burning pain in the muscles,the response of the muscles is to synthesize more

A)lactate.
B)glucose.
C)citric acid.
D)fatty acids.

Question 36

Which of the following compounds CANNOT be formed from fatty acids?

A)Ketones
B)Glucose
C)Acetyl CoA
D)Carbon dioxide

Question 37

Which of the following is a possible fate of acetyl CoA?

A)Degradation to urea
B)Synthesis to glycerol
C)Synthesis to fatty acids
D)Degradation to ammonia

Question 38

Which of the following is NOT an aspect of glycolysis?

A)It is irreversible
B)It generates ATP
C)It occurs in the absence of oxygen
D)It generates two molecules of pyruvate for each molecule of glucose

Question 39

Glycolysis is the conversion of

A)glycogen to fat.
B)glycogen to protein.
C)glucose to pyruvate.
D)glucose to glycogen.

Question 40

Your roommate Demetrius is participating in a weightlifting course and complains of a burning pain during workouts.You explain to Demetrius that the rapid breakdown of glucose in his muscles produces large amounts of pyruvate,which leads to a fall in pH within the muscle and that the muscle responds by converting excess pyruvate to

A)lactate.
B)glycerol.
C)acetyl CoA.
D)amino acids.

Question 41

Which of the following products is NOT generated via the TCA cycle or electron transport chain?

A)Water
B)Energy
C)Ammonia
D)Carbon dioxide

Question 42

An immediate consequence of a cellular deficiency of oxaloacetate is a slowing of

A)glycolysis.
B)the TCA cycle.
C)lactate synthesis.
D)ketone formation.

Question 43

At what point is oxygen used in the electron transport chain?

A)At the end
B)At every step
C)At the beginning
D)When ATP is synthesized

Question 44

How many acetyl CoA molecules may be obtained from oxidation of an 18-carbon fatty acid?

A)3
B)6
C)9
D)18

Question 45

Which of the following dietary components CANNOT be used to synthesize and store glycogen?

A)Lactose
B)Animal fats
C)Wheat starch
D)Plant protein

Question 46

Approximately what percentage of the weight of triglycerides CANNOT be converted to glucose?

A)70
B)80
C)90
D)95

Question 47

When energy-yielding nutrients are consumed in excess,which one(s)can lead to storage of fat?

A)Fat only
B)Carbohydrate only
C)Fat and carbohydrate only
D)Fat,carbohydrate,and protein

Question 48

Which of the following CANNOT be used to make body proteins?

A)Glucose
B)Glycerol
C)Fatty acids
D)Amino acids

Question 49

All of the following may serve as precursors for oxaloacetate synthesis EXCEPT

A)fat.
B)starch.
C)glucose.
D)protein.

Question 50

What are the products from the complete oxidation of fatty acids?

A)Urea and acetone
B)Fatty acids and glycerol
C)Carbon,hydrogen,and oxygen
D)Water,carbon dioxide,and energy

Question 51

In addition to energy,what are the principal end products of cellular oxidation of carbohydrates?

A)Water and carbon dioxide
B)Carbon,hydrogen,and urea
C)Indigestible fiber and nitrogen
D)Monosaccharides and amino acids

Question 52

When protein consumption is in excess of body needs and energy needs are met,the excess amino acids are metabolized and the energy in the molecules is

A)stored as fat only.
B)excreted in the feces.
C)stored as amino acids only.
D)stored as glycogen and fat.

Question 53

If the carbohydrate content of the diet is insufficient to meet the body's needs for glucose,which of the following can be converted to glucose?

A)Fatty acids
B)Acetyl CoA
C)Amino acids
D)Carbon dioxide

Question 54

What percentage (by weight)of a triglyceride molecule can be converted to glucose?

A)0
B)5
C)50
D)100

Question 55

Which of the following is a feature of the electron transport chain?

A)It captures energy in the high-energy bonds of ATP
B)It pumps carbon dioxide across the mitochondrial membrane
C)It is composed of a series of coenzymes that transfer electrons up a concentration gradient
D)It combines oxygen from carbon dioxide with hydrogen generated from the splitting of water

Question 56

After digestion and absorption,an amino acid not used to build protein will first be subjected to

A)removal of its amino group.
B)removal of its carboxyl group.
C)hydrolysis of its peptide bond.
D)condensation of its peptide bond.

Question 57

What is the immediate fate of excess dietary protein in the body?

A)Stored
B)Reduced
C)Oxidized
D)Deaminated

Question 58

Which of the following is NOT a product from the electron transport chain pathway?

A)CO₂
B)Urea
C)Water
D)Energy

Question 59

Which of the following leads to the production of urea?

A)Oxidation of glucose
B)Oxidation of amino acids
C)Incomplete oxidation of fatty acids
D)Synthesis of protein from amino acids

Question 60

Where do the TCA cycle reactions take place?

A)Golgi
B)Endoplasmic reticulum
C)Nucleus of the mitochondria
D)Inner compartment of the mitochondria

Question 61

After the first day or so of fasting,which of the following is most depleted in the body?

A)Glycogen
B)Fatty acids
C)Amino acids
D)Triglycerides

Question 62

Which of the following is a feature of the metabolism of surplus dietary fat?

A)Excess fat is almost all stored
B)Excess fat promotes increased fat oxidation
C)Excess fat spares breakdown of body proteins
D)Conversion of excess fat to storage fat is inefficient

Question 63

The number of ATP molecules that can be produced from a molecule of protein,fat,or carbohydrate is generally related to the number of atoms of

A)carbon.
B)oxygen.
C)nitrogen.
D)hydrogen.

Question 64

How does excess carbohydrate intake contribute to obesity?

A)It is efficiently converted to storage fat
B)It spares oxidation of body fat and dietary fat
C)It stimulates glucagon release,resulting in inhibition of fatty acid oxidation
D)It stimulates pancreatic lipase secretion,which results in higher dietary fat absorption

Question 65

Jake is getting ready for spring training and is sitting down to a dinner of half a chicken,a rib-eye steak,black beans,and 5 slices of bacon.He has been eating typical dinners like this for about a month and has since gained 7 pounds,while exercising only briefly.When Jake asks why he doesn't see an increase in his biceps or abs,the proper response should be

A)dietary protein alone does not contribute to muscle accretion.
B)it takes at least 6 months to document changes in muscle accretion.
C)the weight he has gained can be attributed to a substantial increase in his protein stores.
D)because muscle accretion only responds to very lean meat choices,he should eliminate the fatty bacon and steak from his diet to promote muscle gain.

Question 66

During the first few days of a fast,what energy source provides about 90% of the glucose needed to fuel the body?

A)Protein
B)Ketones
C)Glycogen
D)Triglycerides

Question 67

If a person consumes 100 kcalories in excess of energy needs from table sugar,approximately how many of the kcalories are stored in the body?

A)25
B)50
C)75
D)100

Question 68

How soon would death occur from starvation if the body was unable to shift to a state of ketosis?

A)Within 3 weeks
B)Less than 2 weeks
C)Between 5 and 6 weeks
D)Between 2 and 3 months

Question 69

Which of the following can be synthesized from all three energy-yielding nutrients?

A)Lactate
B)Glycogen
C)Acetyl CoA
D)Oxaloacetate

Question 70

Which of the following accounts for the higher energy density of a fatty acid compared with the other energy-yielding nutrients?

A)Fatty acids have a lower percentage of hydrogen-carbon bonds
B)Fatty acids have a greater percentage of hydrogen-carbon bonds
C)Other energy-yielding nutrients have a lower percentage of oxygen-carbon bonds
D)Other energy-yielding nutrients undergo fewer metabolic reactions,thereby lowering the energy yield

Question 71

Which of the following is the body's first response to the absorption of abundant amounts of carbohydrate?

A)Catabolism of body fat
B)Catabolism of glycogen
C)Synthesis and storage of glycogen
D)Synthesis and storage of triglycerides

Question 72

If a normal person expends 1200 kcalories while at rest,approximately how many are used by the brain?

A)40
B)100
C)200
D)300

Question 73

Which of the following is a characteristic of the metabolism of specific macronutrients?

A)The rate of fat oxidation does not change when fat is eaten in excess
B)The rate of protein oxidation does not change when protein is eaten in excess
C)The rate of glucose oxidation does not change when carbohydrate is eaten in excess
D)The conversion of dietary glucose to fat is the major pathway of carbohydrate utilization

Question 74

If a person consumes 100 kcalories in excess of energy needs from olive oil,approximately what percentage of the kcalories are stored in the body?

A)25
B)45
C)65
D)95

Question 75

Approximately how many molecules of ATP are generated from the complete oxidation of one molecule of glucose?

A)4
B)9
C)32
D)130

Question 76

Which of the following is the most likely explanation for the body's higher metabolic efficiency of converting a molecule of corn oil into stored fat compared with a molecule of sucrose?

A)The enzymes specific for metabolizing absorbed fat have been found to have higher activities than those metabolizing sucrose
B)The absorbed corn oil is transported to fat cells at a faster rate than the absorbed sucrose,thereby favoring the uptake of corn oil fat
C)There are fewer metabolic reactions for disassembling the corn oil and re-assembling the parts into a triglyceride for uptake by the fat cells
D)Because corn oil has a greater energy content than sucrose,conversion of these nutrients into stored fat requires a smaller percentage of the energy from the corn oil

Question 77

Which of the following dietary nutrients would most rapidly reverse a state of ketosis in a starving person?

A)Fat
B)Protein
C)Amino acids
D)Carbohydrate

Question 78

Approximately how many ATP molecules are synthesized from the complete oxidation of a molecule of palmitic acid?

A)9
B)27
C)98
D)129

Question 79

Of the total amount of carbohydrate energy consumed by the body,approximately what percentage is used by the brain and nerve cells?

A)10
B)30
C)50
D)90

Question 80

All of the following are features of the metabolism of surplus dietary carbohydrate in human beings EXCEPT

A)excess glucose suppresses fat oxidation.
B)excess glucose is oxidized only very slowly.
C)excess glucose is first used to fill glycogen reserves.
D)conversion of excess glucose to fat occurs only to a very limited extent.