BIO 122 Metabolism Unit

During cellular respiration, how much of the original energy in the glucose molecule is transferred into ATP and how much is instead converted into (lost as) heat? 25% to ATP and 75% to heat. 40% to ATP and 60% to heat. 50% to ATP and 50% to heat. 60% to ATP and 40% to heat.

40% to ATP and 60% to heat.

Niacin (vitamin B3) is important for ATP synthesis because it forms NAD. What specific role does NAD play in energy metabolism? It removes water during the Krebs cycle. It transfers hydrogens released during glycolysis and Krebs cycle to the electron transport system. It removes CO2 during the Krebs cycle. It breaks down glucose.

It transfers hydrogens released during glycolysis and Krebs cycle to the electron transport system.

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

a) postabsorptive

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. c) hydrolyze glucose. d) produce carbon dioxide. e) produce water.

a) remove hydrogen atoms from organic molecules and transfer them to coenzymes.

Impaired fat absorption in the intestine would interfere with the absorption of a) vitamin A. b) vitamin B12. c) vitamin C. d) niacin. e) riboflavin.

a) vitamin A.

Ketone bodies can result from excess production of: glucose. acetyl CoA. pyruvic acid. fats.

acetyl CoA.

Amino acids and fatty acids may enter the citric acid cycle by way of: gylcerol. NAD. pyruvic acid. acetyl-CoA

acetyl-CoA

Regulation of body temperature is controlled by: shivering vasodilation of cutaneous vessels is regulated by a center in the hypothalamus all of the above

all of the above

Pellagra, an epithelial and mucosal deterioration, results from a deficiency in a) vitamin B2 (riboflavin). b) vitamin B3 (niacin). c) vitamin B9 (folic acid). d) vitamin D. e) vitamin K.

b) vitamin B3 (niacin).

Which of the following is the first step in ATP production from fat? beta-oxidation glycolysis deamination phosphorylation

beta-oxidation

Linoleic acid and linolenic acid are examples of a) transport proteins. b) lipoproteins. c) essential fatty acids. d) essential amino acids. e) vitamins.

c) essential fatty acids.

The vitamin that is a coenzyme in amino acid and nucleic acid metabolism is a) pantothenic acid. b) pyridoxine (B6). c) folic acid (folate). d) vitamin C. e) vitamin K.

c) folic acid (folate).

Where does the breakdown of glucose to pyruvic acid occur? nucleus cytoplasm mitochondria cell membrane

cytoplasm

Where in a cell does glycolysis occur? cytoplasm mitochondrial matrix mitochondrial cristae nucleus

cytoplasm

Blood glucose levels are increased by: glycogenolysis glycogenesis insulin glycosuria

glycogenolysis

When the blood glucose level becomes low, which of the following would most likely increase? glycogenesis glycogenolysis glycolysis glycosuria

glycogenolysis

If the cell starts with fat as its fuel source, which of the following reactions will NOT occur? glycolysis electron transport citric acid cycle (Krebs cycle) Beta-oxidation

glycolysis

Which of the following carry excess cholesterol from peripheral tissues to the liver? a) Very-low-density lipoproteins (VLDLs) b) Low-density lipoproteins (LDLs) d) High-density lipoproteins (HDLs)

d) High-density lipoproteins (HDLs)

Lipogenesis generally begins with a) glucose. b) amino acids. c) fatty acids. d) acetyl-CoA.

d) acetyl-CoA.

The minimum resting energy expenditure of an awake, alert person is called a) body mass index rate. b) homeostasis. c) steady state. d) basal metabolic rate. e) stasis.

d) basal metabolic rate.

The process that catabolizes fatty acids to acetyl-CoA is called a) lipolysis. b) lipogenesis. c) emulsification d) beta-oxidation.

d) beta-oxidation.

The lipoproteins that carry absorbed lipids from the intestinal tract to the bloodstream are the a) high-density lipoproteins (HDLs). b) very-low-density lipoproteins (VLDLs). c) low-density lipoproteins (LDLs). d) chylomicrons.

d) chylomicrons.

The process of synthesizing glucose from noncarbohydrates is called a) glycogenolysis. b) glycogenesis. c) glycolysis. d) gluconeogenesis.

d) gluconeogenesis.

At the Holy Frijoles restaurant, you order a burrito grande with extra sour cream and cheese and an order of tortilla chips with guacamole. You're very satisfied with your meal—it's a lot of food—and as you finish off the last of the chips, the satiety center in your ________ starts letting you know that you've had enough to eat now. a) cerebellum b) pons c) mid-brain d) hypothalamus e) medulla oblongata

d) hypothalamus

The energy content of foods is commonly given in units of a) ATP units. b) carbohydrate. c) grams (also, g, or gms). d) kilocalories (also, kcal or Cal). e) degrees Celsius.

d) kilocalories (also, kcal or Cal).

A chemical reaction by which the -NH2 group is removed from an amino acid is known as: isomerization. hydrolysis. deamination. oxidation.

deamination.

ATP can be used for a) muscle contraction. b) ion transport. c) protein synthesis. d) glycogen synthesis. e) All of the answers are correct.

e) All of the answers are correct.

The food pyramid recommends many servings a day of dark-green and orange vegetables. Which vitamin is particularly abundant in this food group? a) A b) C c) E d) folic acid e) All of the answers are correct.

e) All of the answers are correct.

The vitamin that prevents breakdown of vitamin A and fatty acids is vitamin a) A. b) B. c) C. d) D. e) E.

e) E.

the largest lipoproteins, ________, are produced by intestinal epithelial cells from the fats in food. a) very-low-density lipoproteins (VLDLs) b) low-density lipoproteins (LDLs) d) high-density lipoproteins (HDLs) e) chylomicrons

e) chylomicrons

A disorder caused by the ingestion of excessive quantities of a fat-soluble vitamin is known as a) protein deficiency disease. b) Kwashiorkor. c) avitaminosis. d) carbohydrate loading. e) hypervitaminosis.

e) hypervitaminosis.

During cellular respiration, which set of reactions produces water? glycolysis citric acid cycle electron transport Krebs cycle

electron transport

Most of the ATP in our cells is produced during: electron transport. photosynthesis. beta-oxidation. glycolysis.

electron transport.

In the absence of oxygen, what is produced at the end of glycolysis? acetyl coenzyme A carbon dioxide lactic acid pyruvic acid

lactic acid

In skeletal muscle, one major disadvantage of relying solely on glycolysis under anaerobic conditions is that: lactic acid accumulates in the muscle. ATP cannot be produced. without oxygen, glucose cannot be broken down. CO and alcohol are the final products.

lactic acid accumulates in the muscle.

When a cell needs energy, glycogen may be hydrolyzed to: many disaccharides. two fatty acid molecules. many glycerol molecules. many glucose molecules.

many glucose molecules.

Coenzyme A is derived from: pantothenic acid (Vitamin B5). thiamin. ATP. cytochromes.

pantothenic acid (Vitamin B5).

The carbohydrates in an uneaten candy bar can best be described as: exothermic energy. kinetic energy. potential energy. ATP energy.

potential energy.

The mitochondria are often called the "powerhouses" of the cell because they: synthesize glucose. produce most of the ATP (cell energy) generated from glucose. are where glycolysis, Krebs cycle, and electron transport all occur. conduct glycolysis, and therefore other pathways as well, which has to occur before any ATP can be produced.

produce most of the ATP (cell energy) generated from glucose.

The process by which electrons are transferred from NAD through various cytochromes and finally to oxygen occurs to: rid cells of excess oxygen molecules. form ketone bodies from beta-oxidation. provide energy for ATP formation. convert glucose into glycogen.

provide energy for ATP formation.

The increase in body temperature during exercise: results from a greatly increased metabolism occurs when the body is not producing enough heat normally is due to failure of heat loss mechanisms occurs only during running exercises

results from a greatly increased metabolism

Basal metabolism most directly refers to the energy output required: to maintain basic body functions for growth of a child during old age during exercise

to maintain basic body functions

________ contains all of the essential amino acids. A fat-soluble vitamin A water-soluble vitamin An essential fatty acid A carbohydrate A complete protein

A complete protein

All cells use which of the following directly for energy to fuel their work? glycogen. ATP. sunlight. glucose.

ATP.

The molecule that supplies our cells with an immediate source of energy is: glucose. glycogen. ATP. monosaccharide.

ATP.

Acetyl CoA for the citric acid cycle may be formed through metabolism of: fatty acids glucose amino acids All of the above None of the above

All of the above

________ is deficient in one or more of the essential amino acids. A complete protein A water-soluble vitamin An incomplete protein A fat-soluble vitamin

An incomplete protein

Which of the following is calculated directly by using a person's height and weight? basal metabolic rate rate of ATP production BMI energy (caloric) needs

BMI

A decrease in body weight occurs when more calories are consumed than is necessary to meet the metabolic requirements of the cells. True False

False

An adult weighing 130 lb. requires the same amount of energy to walk up a flight of stairs as does an adult weighing 280 lb. True. The distance is the same so the energy expended is equal with the two individuals. False. It requires more energy for the larger adult because he/she has a higher BMI. False. It requires less energy for the larger adult because he/she has more muscle. False. It requires more energy for the larger adult because he/she is out of shape.

False. It requires more energy for the larger adult because he/she has a higher BMI.

Which of the following statements is true about carbohydrates? They contain carbon, hydrogen, and oxygen and the simplest form is a disaccharide. Their main use is to provide energy. They are stored in adipose tissue as fatty acids. All of the above are true. A and B only

Their main use is to provide energy.

Urea is formed in the a) liver. b) stomach. c) kidneys. d) small intestine. e) large intestine.

a) liver.

The vitamin that plays a role in maintaining epithelia and is required for the synthesis of visual pigments is vitamin a) A. b) B. c) C. d) D. e) E.

a) A.

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. d) contains enzymes called cytochromes. e) forms acetyl-CoA from glucose-6-phosphate.

a) begins with the formation of a molecule of citric acid.

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.

a) gout.

All of the following take place during the absorptive state except a) ketone bodies begin to form. b) blood glucose levels rise. c) blood lipid levels rise. d) insulin stimulates glycogenesis.

a) ketone bodies begin to form.

Deficiency in what vitamin can result in a condition called scurvy? a) A b) C c) B12 d) D

b) C

Fatty acids that are necessary for proper health but cannot be synthesized by the body are called a) water-soluble vitamins. b) essential fatty acids. c) high-density lipoproteins. d) low-density lipoproteins. e) chylomicrons.

b) essential fatty acids.

Although other nutrients can feed into the citric acid cycle, ________ yields energy the quickest. a) glycogen b) glucose c) protein d) fat

b) glucose

All of the following are reasons why glucose is the primary energy source for cells except a) glucose is a small, soluble molecule. b) glycogen breakdown occurs very slowly. c) glucose can be stored efficiently. d) glycogen breakdown involves only a single enzymatic step. e) glycolysis does not require oxygen to generate ATP.

b) glycogen breakdown occurs very slowly.

The hormone ________, which suppresses appetite and stimulates satiety, is released by adipose tissue. a) ghrelin b) leptin c) neuropeptide Y d) insulin e) estrogen

b) leptin

All of the following occur during the postabsorptive state except that a) glycogen is broken down into glucose in the liver. b) levels of blood glucose are elevated. c) ketone bodies may be formed. d) lipid mobilization may occur.

b) levels of blood glucose are elevated.

Resting energy expenditure is most directly determined by monitoring a) heart rate. b) respiration. c) body temperature. d) blood pressure. e) body weight.

b) respiration.

The carbon dioxide of respiration is formed during a) glycolysis. b) the citric acid cycle. c) electron transport. d) all of the above

b) the citric acid cycle.

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.

b) triglycerides are broken down into glycerol and fatty acids.

The conversion of ammonia into a less toxic substance produces a) ketone bodies. b) urea. c) nitrate. d) acetyl-CoA. e) water.

b) urea.

In a healthy individual who has just finished eating a large nutrient-balanced meal: glucagon enhances the absorption of glucose from the intestinal tract insulin increases the excretion of glucose in the urine blood plasma will have an increased concentration of fats, glucose, and amino acids insulin decreases the entrance of glucose into most tissue cells

blood plasma will have an increased concentration of fats, glucose, and amino acids

The process(es) that occur(s) in the mitochondria is/are: glycolysis. Krebs cycle. electron transport. all of the above both b and c

both b and c

Cellular respiration is best described as the: exchange of air between the lungs and the atmosphere. synthesis of glucose using the energy of ATP. breakdown of glucose into CO2 and H2O and production of ATP. conversion of CO2 and H2O into ATP.

breakdown of glucose into CO2 and H2O and production of ATP.

It's been 5 hours since you had breakfast and now you're thinking about trying the new Mexican lunch place that just opened up across the street. The more you think about it, the hungrier you get. That's the result of the ________ that your empty stomach is releasing into your bloodstream. a) cholecystokinin (CCK) b) leptin c) ghrelin d) pepsin e) insulin

c) ghrelin

The area of the brain that regulates body temperature is the a) medulla oblongata. b) pineal gland. c) hypothalamus. d) cerebral cortex. e) pons

c) hypothalamus.

All of the following are true of beta-oxidation except that a) it occurs in the mitochondria. b) fatty acids break down into acetyl-CoA that enter the citric acid cycle. c) lipids are converted into glycogen molecules. d) it requires coenzyme A, NAD, and FAD. e) it ultimately yields large amounts of ATP.

c) lipids are converted into glycogen molecules.

The nutrients that yield the most energy per gram when metabolized are a) carbohydrates. b) proteins. c) lipids. d) nucleic acids. e) vitamins.

c) lipids.

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) None of the answers is correct.

c) the mitochondria

Homeostatic control of body temperature is termed a) thermic monitoring. b) energetics. c) thermoregulation. d) basal metabolic rate.

c) thermoregulation.

In transamination, the amino group of an amino acid is ________, yielding a different amino acid. a) converted to ammonia b) converted to urea c) transferred to another molecule d) absorbed by water

c) transferred to another molecule

During cellular respiration, which set of reactions releases carbon dioxide? glycolysis citric acid (Krebs) cycle electron transport none of them produce carbon dioxide

citric acid (Krebs) cycle

Where in the cell does electron transport occur? matrix of mitochondria cytoplasm cell membrane cristae of mitochondria

cristae of mitochondria

There are ________ essential amino acids that the body either cannot synthesize or that cannot be produced in amounts sufficient for growing children. a) 2 b) 6 c) 8 d) 10 e) 20

d) 10

Obesity is defined as a body weight more than ________ percent above the ideal body weight for an individual. a) 5 b) 10 c) 15 d) 20

d) 20

Glycolytic breakdown of glucose first results in ________ molecules. a) 2 pyruvate (pyruvic acid) b) 2 NADH c) 2 ATP (net) d) All of the answers are correct

d) All of the answers are correct

A person decides to go on a hunger strike to further one of his favorite causes. After many days with nothing but water you would expect to observe a) elevated levels of glucocorticoids. b) ketone bodies in his urine. c) lowered blood pH. d) All of the answers are correct. e) None of the answers is correct.

d) All of the answers are correct.

Cells synthesize new organic components for which of the following reasons? a) structural maintenance b) growth and repair c) production of secretions d) All of the answers are correct. e) None of the answers is correct.

d) All of the answers are correct.

Glucocorticoids have which of the following effects on general peripheral tissues? a) They increase the conversion of amino acids to pyruvate. b) They increase gluconeogenesis. c) They increase glycogenolysis. d) All of the answers are correct.

d) All of the answers are correct.

Inadequate exposure to sunlight can result in decreased amounts of vitamin ________ in the body. a) A b) B12 c) C d) D e) E

d) D

Decreasing blood glucose is a stimulus for the secretion of: epinephrine glucagon growth hormone all of the above

glucagon

Which of the following hormones is most directly involved during the post-absorptive state? glucagon insulin thyroid hormone only by radiation glycogen

glucagon

The conversion of glycerol and amino acids into glucose in called: gluconeogenesis glycogenesis glycolysis glycogenolysis

gluconeogenesis

During the absorptive phase of metabolism: fats are broken down into glycerol and keto acids glucose is the primary energy source for most cells glycogen is converted to glucose there is an increase in ketones

glucose is the primary energy source for most cells

Which of the following is most likely to occur if blood glucose levels are elevated? gluconeogenesis glycogenesis glycogenolysis all the above

glycogenesis

A political prisoner has been on a hunger strike for seven days. Compared to normal, he has: increased release of fatty acids from adipose tissue elevated glucose concentration in the blood increased plasma insulin concentration increased glycogen storage in the liver

increased release of fatty acids from adipose tissue

Temperature regulation is: influenced by peripheral thermoreceptors in the skin primarily regulated by conductive heat loss independent of hormonal influences accomplished primarily by regulating heat gain

influenced by peripheral thermoreceptors in the skin

A decrease in body weight occurs when caloric intake: equals basal metabolism plus external work is greater than basal metabolism plus external work is less than basal metabolism plus external work is less than basal metabolism plus internal work

is less than basal metabolism plus external work

Body temperature: is always constant except when one has a fever is regulated primarily by regulating heat loss regulation by evaporation of sweat is important only during exercise none of the above

is regulated primarily by regulating heat loss

Epinephrine: is released from the adrenal medulla and acts to stimulate glycogenolysis levels in the blood decrease with dieting decreases glucose levels in the blood increases lipid storage

is released from the adrenal medulla and acts to stimulate glycogenolysis

Which of the following describes the role of NADH during cellular respiration? it produces the oxygen needed for aerobic respiration it carries carbon dioxide to the mitochondria it carries hydrogen to the site of electron transport reactions it transports glucose to the mitochondria for use in cellular respiration

it carries hydrogen to the site of electron transport reactions

Low-density lipoproteins function to: transport cholesterol to cells for use in plasma membranes or hormone synthesis transport cholesterol to the liver for removal assist lacteals in the absorption of fatty acids lower cholesterol levels

transport cholesterol to cells for use in plasma membranes or hormone synthesis

True or False: When ATP breaks down, the products can then be used to synthesize more ATP. True False, because ADP --> ATP + P. False, because ATP --> glucose. False, because ATP --> ADP + ADP.

true

Which of the following is an end product of the electron transport chain? glucose carbon dioxide water NADH

water

The metabolic rate of an individual may be lower than the BMR during exercise while sleeping during the postabsorptive state metabolic rate will never be less than BMR

while sleeping