Deck 17: Metabolism and Energetics

Question 1

Performance in endurance sports improves if muscles have large stores of

A)nucleic acids.
B)protein reserves.
C)lipid reserves.
D)amino acids.
E)carbohydrate reserves.

Answer 1

E

Question 2

The synthesis of new organic molecules,involving the formation of new chemical bonds,is called

A)glycolysis.
B)catabolism.
C)anabolism.
D)differentiation.
E)lipolysis.

Answer 2

C

Question 3

About 40% of the energy released through catabolism is used to convert ADP to ATP.What happens to the remaining 60% of energy?

A)It is destroyed during the catabolic activities.
B)It is used to convert RNA to DNA.
C)It is immediately used in anabolic processes.
D)It escapes as heat to warm the tissues.
E)It transforms into mechanical energy.

Answer 3

D

Question 4

When actively contracting,skeletal muscles catabolize glucose,but at rest they rely on which of the following?

A)proteins
B)glycogen
C)nucleic acids
D)fatty acids
E)amino acids

Question 5

Which of the following is the first intermediate formed in the citric acid cycle?

A)coenzyme A
B)pyruvate
C)FADH₂
D)citric acid
E)oxygen

Question 6

Which of the following may not be used for gluconeogenesis because their breakdown produces acetyl CoA?

A)fatty acids
B)complex carbohydrates
C)glycerol
D)nucleic acids
E)glycogen

Question 7

Place the following steps of the electron transport system (ETS)and ATP formation in the correct order. 1.Movement of hydrogen ions provides energy to ATP synthesis.
2.Electrons from FADH₂ pass to coenzyme Q.
3.Electrons are transported to respiratory complex III.
4.ADP combines with P to form ATP.
5.Electrons from NADH pass to coenzyme Q.
6.Electrons combine with oxygen and hydrogen ions to form water molecules.

A)6,3,5,2,4,1
B)5,2,3,6,1,4
C)1,2,6,4,3,5
D)4,6,1,3,5,2
E)2,3,6,5,4,1

Question 8

During glycolysis in the cytoplasm,the cell gains how many molecules of ATP for each glucose molecule broken down to pyruvate?

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

Question 9

Most cells generate ATP and other high-energy compounds by breaking down carbohydrates,especially

A)ribose.
B)galactose.
C)sucrose.
D)fructose.
E)glucose.

Question 10

Regarding the citric acid cycle,which molecule participates in a complex reaction involving NAD and coenzyme A within the mitochondrion?

A)pyruvate
B)citric acid
C)ATP
D)oxygen
E)FADH₂

Question 11

The ion(s)or molecule(s)labeled B is (are)

A)CO₂.
B)H₂O.
C)O₂.
D)H⁺.
E)2H.

Question 12

Cyanide poisoning quickly leads to death because it blocks the final cytochrome molecule in the electron transport system.Why is this blockage lethal?

A)All hydrogen ion pumps deactivate.
B)NADH molecules cannot give off their electrons.
C)FADH₂ molecules cannot give off their electrons.
D)Electrons cannot transfer to oxygen.
E)Coenzyme Q disassociates and becomes nonfunctional.

Question 13

Gluconeogenesis is the synthesis of glucose from precursor molecules such as

A)sucrose.
B)glycerol.
C)fructose.
D)glycogen.
E)galactose.

Question 14

The ion(s)or molecule(s)labeled C is (are)

A)CO₂.
B)H₂O.
C)O₂.
D)H⁺.
E)2H.

Question 15

In the liver and skeletal muscles,glucose molecules are stored as

A)triglycerides.
B)fatty acids.
C)pyruvate.
D)sucrose.
E)glycogen.

Question 16

Carbohydrate metabolism involves the reactants,glucose plus oxygen,and the resultant products

A)pyruvate and nitrogen.
B)carbon dioxide and water.
C)water and sucrose.
D)nitrogen and hydrogen.
E)water and pyruvate.

Question 17

In the electron transport system (ETS),which of the following are pumped into the intermembrane space,providing the concentration gradient essential for the generation of ATP?

A)oxygen molecules
B)water molecules
C)ATP molecules
D)hydrogen ions
E)cytochromes

Question 18

The sum of all of the chemical reactions occurring within the human body is called

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

Question 19

For each molecule of glucose processed,a typical cell gains ________ molecules of ATP.

A)2-3
B)6-8
C)15-16
D)30-32
E)60-64

Question 20

The ion(s)or molecule(s)labeled A is (are)

A)CO₂.
B)H₂O.
C)O₂.
D)H⁺.
E)2H.

Question 21

Molecules that carry excess cholesterol from peripheral tissues to the liver for storage or secretion in the bile are called

A)low-density lipoproteins (LDLs).
B)high-density lipoproteins (HDLs).
C)fatty acids.
D)steroids.
E)chylomicrons.

Question 22

The ion(s)or molecule(s)labeled G is (are)

A)CO₂.
B)H₂O.
C)O₂.
D)H⁺.
E)2H.

Question 23

The ion(s)or molecule(s)labeled D is (are)

A)CO₂.
B)H₂O.
C)O₂.
D)H⁺.
E)2H.

Question 24

Due to an enzyme defect,individuals with phenylketonuria cannot convert the amino acid phenylalanine to

A)urea.
B)tyrosine.
C)ketones.
D)serotonin.
E)ATP.

Question 25

Which is accurate regarding ketoacidosis?

A)Blood pH may drop below 7.05.
B)Blood pH may rise to 9.05.
C)Blood pH is not affected.
D)Increased alkalinity of body tissues occurs.
E)Conditions do not ever become so severe that coma results.

Question 26

Which of the following delivers cholesterol to peripheral tissues?

A)triglycerides
B)low-density lipoproteins
C)high-density lipoproteins
D)free fatty acids
E)glycerol groups

Question 27

The ion(s)or molecule(s)labeled F is (are)

A)CO₂.
B)H₂O.
C)O₂.
D)H⁺.
E)2H.

Question 28

In transamination,the amino group of an amino acid is transferred to

A)ammonia.
B)urea.
C)another carbon chain.
D)a molecule in the glycolytic pathway.
E)acetyl CoA.

Question 29

Which of the following is the maximum "healthy" cholesterol level in a typical 19-year-old male?

A)230 mg/dL
B)185 mg/dL
C)200 mg/dL
D)350 mg/dL
E)250 mg/dL

Question 30

Beta-oxidation

A)occurs in the mitochondria and is a series of reactions that break down fatty acids.
B)breaks down proteins into two-carbon fragments that can be metabolized by the citric acid cycle.
C)yields large amounts of ATP,while requiring coenzyme A,NAD,and FAD.
D)occurs during glycolysis and generates NAD and FAD molecules.
E)is the final step of the citric acid cycle where hydrogen ions enter the electrons transport system.

Question 31

Glycerol enters the citric acid cycle after enzymes in the cytosol convert it to

A)glucose.
B)pyruvate.
C)glycogen.
D)LDL/HDL.
E)cholesterol.

Question 32

Lipids that can diffuse easily across plasma membranes are called

A)triglycerides.
B)steroids.
C)albumins.
D)high-density lipoproteins.
E)free fatty acids.

Question 33

Protein catabolism is an impractical source of quick energy because

A)the major byproduct is hydrogen,which cells cannot use for energy.
B)proteins are unimportant to cellular homeostasis.
C)the body cannot synthesize any of the amino acids,which it needs.
D)proteins are catabolized much too easily,resulting in homeostatic imbalance.
E)proteins are more difficult to catabolize than are complex carbohydrates or lipids.

Question 34

Lipid catabolism yields 1.3 times as much ATP compared to aerobic glucose metabolism.So why is lipid catabolism not the prime source of ATP in the human body?

A)Most people do not have enough lipid reserves.
B)Water-soluble enzymes cannot easily get to the lipid droplets.
C)Lipid catabolism occurs in the cytosol where oxygen availability is limited.
D)Lipid catabolism occurs primarily during times of starvation.
E)Lipid catabolism produces large amounts of nitrogenous wastes,which are taxing on the liver.

Question 35

A cell produces how many ATP molecules from the breakdown of one 18-carbon fatty acid molecule?

A)4
B)16
C)120
D)32
E)60

Question 36

Which of the following is never catabolized for energy,even in cells dying of starvation?

A)DNA
B)proteins
C)rRNA
D)tRNA
E)mRNA

Question 37

The process of deamination produces

A)keto acids.
B)high levels of proteins.
C)an ammonium ion.
D)acetyl CoA.
E)B vitamins.

Question 38

The ion(s)or molecule(s)labeled E is (are)

A)CO₂.
B)H₂O.
C)O₂.
D)H⁺.
E)2H.

Question 39

Synthesis of ________ occurs only in cells preparing for mitosis or meiosis.

A)ribosomal RNA (rRNA)
B)cholesterol
C)messenger RNA (mRNA)
D)DNA
E)transfer RNA (tRNA)

Question 40

Lipogenesis of steroids and almost all fatty acids begins with

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

Question 41

________ are inorganic ions released through electrolytes,such as sodium chloride.

A)Minerals
B)Enzymes
C)Water-soluble vitamins
D)Essential proteins
E)Fat-soluble vitamins

Question 42

Which of the following comprise the best source of vitamin C?

A)milk and meat
B)bread and potatoes
C)vegetables
D)citrus fruits
E)breads and cheeses

Question 43

Which of the following is a complete protein source?

A)corn
B)spinach
C)rice
D)eggs
E)oranges

Question 44

________ is a trace mineral that is a component of hemoglobin,myoglobin,and cytochromes.

A)Magnesium
B)Calcium
C)Zinc
D)Copper
E)Iron

Question 45

Which of the following is a trace mineral?

A)chloride
B)sodium
C)calcium
D)iron
E)magnesium

Question 46

Which of the following is a major anion in body fluids,primarily excreted through urine and sweat?

A)sodium
B)chloride
C)potassium
D)calcium
E)zinc

Question 47

Which fat-soluble vitamin is synthesized in skin that is exposed to sunlight?

A)vitamin K
B)vitamin E
C)vitamin B₆ (pyridoxine)
D)vitamin D
E)vitamin C

Question 48

Nucleotides from RNA

A)are deaminated to form ammonia.
B)can provide sugars for glycolysis,in order to form ATP.
C)can be used to synthesize proteins.
D)cannot be used as a source of energy in place of ATP.
E)cannot be recycled.

Question 49

Which bulk mineral is a major cation in body fluids and is essential for normal membrane function?

A)calcium
B)iron
C)sodium
D)chloride
E)phosphorus

Question 50

A mineral that is a necessary cofactor for hemoglobin synthesis is

A)zinc.
B)copper.
C)cobalt.
D)iodine.
E)silicon.

Question 51

A bulk mineral that is essential for normal muscle and neuron function as well as for bone structure is

A)sodium.
B)potassium.
C)calcium.
D)magnesium.
E)selenium.

Question 52

This mineral is a cofactor of the carbonic anhydrase enzyme system.

A)chloride
B)calcium
C)copper
D)zinc
E)magnesium

Question 53

The natural dietary sources for vitamin B₁₂ (cobalamin)are

A)fruits only.
B)meats and milk.
C)vegetables only.
D)breads and potatoes.
E)leafy vegetables.

Question 54

An ion that is a necessary component of high-energy compounds,nucleic acids,and bone matrix is

A)chloride.
B)sulfate.
C)phosphate.
D)bicarbonate.
E)iodide.

Question 55

The vitamin that is a constituent of coenzyme FAD is

A)thiamine (B₁).
B)riboflavin (B₂).
C)niacin (nicotinic acid).
D)folate (B₉).
E)cobalamin (B₁₂).

Question 56

The vitamin that is required for the synthesis of visual pigments is

A)vitamin A.
B)vitamin B.
C)vitamin C.
D)vitamin D.
E)vitamin E.

Question 57

The vitamin that is essential for liver synthesis of prothrombin and other clotting factors is

A)vitamin A.
B)vitamin B.
C)vitamin E.
D)vitamin C.
E)vitamin K.

Question 58

Which of the following is a fat-soluble vitamin?

A)vitamin K
B)vitamin C
C)vitamin B₆
D)niacin
E)riboflavin

Question 59

Hypovitaminosis of vitamin B₁₂ can cause pernicious anemia,however,hypervitaminosis can cause

A)polycythemia.
B)possible lethal CNS alterations.
C)hypotension.
D)kidney stones.
E)itching and tingling sensations.

Question 60

The vitamin that functions as part of coenzyme A is

A)pantothenic acid (B₅).
B)nicotinic acid (B₃).
C)folic acid (B₉).
D)cobalamin (B₁₂).
E)riboflavin (B₂).

Question 61

The vitamin that is a coenzyme in amino acid and lipid metabolism is

A)vitamin B₆ (pyridoxine).
B)vitamin B₅ (pantothenic acid).
C)vitamin B₂ (riboflavin).
D)vitamin B₉ (folic acid).
E)niacin (nicotinic acid).

Question 62

Mucosal deterioration is a sign of hypovitaminosis for vitamins C,B₂,and

A)B₃.
B)A.
C)D.
D)K.
E)C.

Question 63

An average individual has a basal metabolic rate (BMR)of about

A)400 cal/hr.
B)3680 cal/hr.
C)70 cal/hr.
D)7000 cal/day.
E)145 cal/hr.

Question 64

The daily average water requirement for humans is

A)250 ml.
B)2500 ml.
C)500 ml.
D)1500 ml.
E)1000 ml.

Question 65

Which water-soluble vitamin must first be bound to the intrinsic factor secreted by the gastric mucosa before it can be absorbed by the intestinal epithelium?

A)vitamin B₂ (riboflavin)
B)vitamin C (ascorbic acid)
C)vitamin B₁₂ (cobalamin)
D)vitamin B₅ (pantothenic acid)
E)vitamin B₆ (pyridoxine)

Question 66

Which of the following processes of heat transfer is the result of heat loss to the air that overlies the surface of an object?

A)radiation
B)conduction
C)evaporation
D)condensation
E)convection

Question 67

The direct transfer of energy through physical contact is called

A)evaporation.
B)condensation.
C)convection.
D)radiation.
E)conduction.

Question 68

A patient complains of blurred vision and fatigue.A diagnostic exam reveals that she has been taking megadoses of ________ supplements.

A)vitamin K
B)vitamin E
C)vitamin C
D)vitamin A
E)vitamin D

Question 69

A Calorie unit used in food is equal to the amount of energy necessary to raise the temperature of 1 kilogram of water ________ degree(s)Celsius.

A)1
B)2
C)10
D)100
E)1,000

Question 70

Which of the following minerals is a cofactor for some enzymes and is a mineral whose primary route of excretion is through feces and trace amounts in urine?

A)chloride
B)copper
C)iron
D)manganese
E)calcium

Question 71

An example of nonshivering thermogenesis occurs when epinephrine from the adrenal glands immediately increases the breakdown of glycogen in the

A)heart and lungs.
B)liver and skeletal muscles.
C)kidneys and pancreas.
D)skin and accessory glands.
E)hypothalamus and pons.

Question 72

Charlie has a blood test that shows a normal level of LDLs but an elevated level of HDLs in his blood.Since his family has a history of cardiovascular disease,he wonders if he should modify his lifestyle.What should one advise him to do or not to dow?

Question 73

Which of the following activities expends the most calories per hour?

A)speed walking
B)jogging
C)slow walking
D)competitive swimming
E)climbing stairs

Question 74

Beriberi is a degenerative disease caused by a deficiency of ________,having the effects of muscle weakness and CNS and cardiovascular problems including heart disease.

A)vitamin B₁ (thiamine)
B)vitamin B₁₂ (cobalamin)
C)vitamin C (ascorbic acid)
D)niacin (nicotinic acid)
E)vitamin B₂ (riboflavin)

Question 75

The heat-loss and heat-gain centers of the body are found in which of the following?

A)hippocampus
B)medulla oblongata
C)hypothalamus
D)pons
E)cerebellum

Question 76

During times of increased body temperature,which of the following physiological responses is most likely to occur?

A)Vasomotor center is stimulated.
B)Sweat glands decrease their secretions.
C)Respiratory centers are inhibited.
D)Nonshivering thermogenesis is inhibited.
E)Shivering thermogenesis is stimulated.

Question 77

The vitamin that is a coenzyme in amino acid and nucleic acid metabolism is

A)vitamin B₅ (pantothenic acid).
B)vitamin B₆ (pyridoxine).
C)vitamin B₉ (folic acid).
D)vitamin C (ascorbic acid).
E)vitamin K.