Metabolism Bio 122
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
________ contains all of the essential amino acids. A water-soluble vitamin A complete protein A carbohydrate An essential fatty acid A fat-soluble vitamin
A complete protein
All cells use which of the following directly for energy to fuel their work? glycogen. glucose. ATP. sunlight.
ATP.
The molecule that supplies our cells with an immediate source of energy is: glucose. glycogen. ATP. monosaccharide.
ATP.
________ is deficient in one or more of the essential amino acids. An incomplete protein A water-soluble vitamin A fat-soluble vitamin A complete protein
An incomplete protein
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
All of the answers are correct
A balanced diet should a) include adequate substrates for the production of energy. b) provide essential amino acids and fatty acids. c) contain adequate amounts of vitamins and minerals. d) All of the answers are correct.
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.
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.
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.
All of the answers are correct.
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
Lipogenesis generally begins with a) glucose. b) amino acids. c) fatty acids. d) acetyl-CoA.
acetyl-CoA.
Amino acids can be converted into: fatty acids other amino acids. glucose. all of the above
all of the above
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
Which of the following increases the breakdown of triglycerides in adipose tissue? epinephrine thyroid hormone exercise all of the above
all of the above
Where in the cell does electron transport occur? cytoplasm matrix of mitochondria cell membrane cristae of mitochondria
cristae of mitochondria
Poisons like cyanide bind to ________ and prevent electron transfer. a) enzymes b) the endoplasmic reticulum c) acetyl-CoA d) cytochromes
cytochromes
Where does the breakdown of glucose to pyruvic acid occur? cell membrane nucleus cytoplasm mitochondria
cytoplasm
Where in a cell does glycolysis occur? cytoplasm mitochondrial matrix mitochondrial cristae nucleus
cytoplasm
During cellular respiration, which set of reactions produces the most ATP? electron transport glycolysis ventilation citric acid cycle
electron transport
Most of the ATP in our cells is produced during: glycolysis. photosynthesis. beta-oxidation. electron transport.
electron transport.
Which of these is a hormone that causes an increase in blood glucose concentration? glycogen cholesterol epinephrine insulin
epinephrine
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.
essential fatty acids.
Linoleic acid and linolenic acid are examples of a) transport proteins. b) lipoproteins. c) essential fatty acids. d) essential amino acids. e) vitamins.
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.
folic acid (folate).
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? glycosuria glycogenolysis glycogenesis glycolysis
glycogenolysis
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
gout.
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
NAD, which acts as a hydrogen carrier in the cell, is derived from: thiamin. niacin (nicotinic acid). riboflavin. pyruvic acid.
niacin (nicotinic acid).
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
postabsorptive
A person with untreated diabetes mellitus would be in a prolonged: absorptive state postabsorptive state catatonic state hypoglycemic state
postabsorptive state
The carbohydrates in an uneaten candy bar can best be described as: exothermic energy. ATP energy. potential energy. kinetic energy.
potential energy.
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
transferred to another molecule
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: One of the major results of cellular respiration is heat. true false
true
For each molecule of glucose converted to pyruvic acid: two molecules of ATP are broken down and two are synthesized. two molecules of ATP are broken down and four are synthesized. one molecule of ATP is broken down and two are synthesized. one molecule of ATP is broken down and one is synthesized.
two molecules of ATP are broken down and four are synthesized.
The conversion of ammonia into a less toxic substance produces a) ketone bodies. b) urea. c) nitrate. d) acetyl-CoA. e) water.
urea.
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.
vitamin A.
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.
vitamin B3 (niacin).
Which of the following is an end product of the electron transport chain? glucose water carbon dioxide NADH
water
An increased caloric intake without an increase in external expenditure would most likely lead to: weight gain decreased BMR weight loss no change in weight or BMR
weight gain
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
Which of the following is the first step in ATP production from fat? beta-oxidation deamination glycolysis phosphorylation
beta-oxidation
The process that catabolizes fatty acids to acetyl-CoA is called a) lipolysis. b) lipogenesis. c) emulsification d) beta-oxidation.
beta-oxidation.
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
About 60% of the heat loss from a nude person standing in a room at 70 degrees (F) is by radiation. Heat loss in this manner is based on the principal that: body temperature is greater than the surrounding temperature, so the nude person releases more heat than he receives large amounts of air move through the room objects in direct contact with the skin surface will absorb large amount of body heat water on the skin surface which changes from the liquid to vapor phase carries away body heat
body temperature is greater than the surrounding temperature, so the nude person releases more heat than he receives
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
A deficiency in vitamin D would result in which of the following disorders? a) scurvy b) night blindness c) rickets d) pernicious anemia e) pellagra
rickets
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
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
10
What is the net energy yield of the citric acid (Krebs) cycle? 38 ATP 34 ATP 2 ATP 4 ATP
2 ATP
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
20
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? 50% to ATP and 50% to heat. 25% to ATP and 75% to heat. 60% to ATP and 40% to heat. 40% to ATP and 60% to heat.
40% to ATP and 60% to heat.
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
The vitamin that is required for proper bone growth and for calcium absorption and retention is vitamin a) A. b) B. c) C. d) D. e) E.
D
The vitamin that prevents breakdown of vitamin A and fatty acids is vitamin a) A. b) B. c) C. d) D. e) E.
E
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.
Compare glycogenesis and glycogenolysis. (Module 23.7A)
Glycogenesis is the formation of glycogen from glucose. Glycogenolysis is the breakdown of glycogen to glucose.
The "good" type of lipoprotein that carries cholesterol from tissues to liver is: HDL (high-density lipoproteins) MDL (mid-density lipoproteins) VLDL (very low-density lipoproteins) LDL (low-density lipoproteins)
HDL (high-density lipoproteins)
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)
High-density lipoproteins (HDLs)
Which of the following is true about the citric acid, or Krebs, cycle? It is anaerobic It produces 38 ATP. It occurs in the cytoplasm It occurs in the matrix of mitochondria
It occurs in the matrix of mitochondria
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 breaks down glucose. It removes CO2 during the Krebs cycle. It transfers hydrogens released during glycolysis and Krebs cycle to the electron transport system.
It transfers hydrogens released during glycolysis and Krebs cycle to the electron transport system.
What two coenzymes transfer hydrogen atoms to the electron transport chain? (Module 23.4C) pyruvate and acetyl CoA NADP and FAD NAD and FAD ADP and GDP ATP and GTP
NAD and FAD
.Choose the correct statement regarding glycolysis. NAD accepts carbon atoms that can be transferred to mitochondria. It is an aerobic process that breaks down a six-carbon glucose molecule into two three-carbon molecules of pyruvate. There is a net gain of two ATP molecules for each glucose molecule. It occurs in the mitochondrion.
There is a net gain of two ATP molecules for each glucose molecule.
Carbohydrates and proteins may be converted to triglycerides and stored as fat. True. Any calorie containing nutrient can be stored as fat in the body. False. Proteins cannot be converted to fat due to the nitrogen in the amine group. False. Carbohydrates will only be stored as glycogen in the body. False. Triglycerides can only be synthesized from lipids.
True. Any calorie containing nutrient can be stored as fat in the body.
Ketone bodies can result from excess production of: acetyl CoA. fats. glucose. pyruvic acid.
acetyl CoA.
Which of the following does not release hydrogens that are used to make ATP in electron transport? glycolysis conversion of pyruvic acid to acetyl Co-A (pre-citric acid cycle) citric acid cycle all of these release hydrogens for use electron transport
all of these release hydrogens for use electron transport
Growth and repair involve primarily what type of reactions? It depends on which body or cell part is growing or repairing. catabolic anabolic
anabolic
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.
basal metabolic rate.
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.
begins with the formation of a molecule of citric acid.
The following equation represents: C6H12O6 + 6 O2 --------> 6 CO2 + 6 H2O + ATP + heat decomposition. beta-oxidation. cellular respiration. dehydration synthesis.
cellular respiration.
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
chylomicrons
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.
chylomicrons.
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
Which of the following occurs when water is released (lost) during a reaction? catabolic synthesis dehydration hydrolysis catabolic hydrolysis dehydration synthesis
dehydration synthesis
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
ghrelin
Decreasing blood glucose is a stimulus for the secretion of: epinephrine glucagon growth hormone all of the above
glucagon
The process of synthesizing glucose from noncarbohydrates is called a) glycogenolysis. b) glycogenesis. c) glycolysis. d) gluconeogenesis.
gluconeogenesis.
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.
glycogen breakdown occurs very slowly.
The caloric requirements of an athlete training for a marathon would most likely be: equal to that of an elderly person equal to that of an adult who is moderately active greater than the recommended 2000 kcal/day diet for an average adult less than that of an adult who exercises moderately
greater than the recommended 2000 kcal/day diet for an average adult
In which of the following conditions does the hypothalamus fail to function? heat exhaustion heat stroke fever shivering
heat stroke
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.
hypervitaminosis.
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
hypothalamus
The area of the brain that regulates body temperature is the a) medulla oblongata. b) pineal gland. c) hypothalamus. d) cerebral cortex. e) pons
hypothalamus.
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.
ketone bodies begin to form.
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.
kilocalories (also, kcal or Cal).
In the absence of oxygen, what is produced at the end of glycolysis? pyruvic acid lactic acid carbon dioxide acetyl coenzyme A
lactic acid
The hormone ________, which suppresses appetite and stimulates satiety, is released by adipose tissue. a) ghrelin b) leptin c) neuropeptide Y d) insulin e) estrogen
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.
levels of blood glucose are elevated.
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.
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.
lipids.
During starvation (a long-term situation): little or no glycogen is stored in the liver insulin secretion by the pancreas is increased epinephrine stimulates glycogenesis in muscle cells protein synthesis in the liver and muscles is increased
little or no glycogen is stored in the liver
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.
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: convert glucose into glycogen. rid cells of excess oxygen molecules. provide energy for ATP formation. form ketone bodies from beta-oxidation.
provide energy for ATP formation.
Glycolysis breaks down glucose into a) citric acid b) amino acids c) glycerol d) pyruvic acid
pyruvic acid
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.
remove hydrogen atoms from organic molecules and transfer them to coenzymes.
Resting energy expenditure is most directly determined by monitoring a) heart rate. b) respiration. c) body temperature. d) blood pressure. e) body weight.
respiration.
Acetyl CoA is important in cellular metabolism because it: serves as an intermediate in multiple energy pathways, for the metabolism of glucose, fatty acids, and amino acids. releases energy for cell work. is the final acceptor of electrons in the electron transport system.
serves as an intermediate in multiple energy pathways, for the metabolism of glucose, fatty acids, and amino acids.
Most nutrient absorption takes place in the a) small intestine. b) stomach. c) large intestine. d) duodenum. e) liver.
small intestine.
The carbon dioxide of respiration is formed during a) glycolysis. b) the citric acid cycle. c) electron transport. d) all of the above
the citric acid cycle.
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.
the mitochondria
Reactions within ________ provide most of the energy needed by a typical cell. the cytoplasm the nucleus the mitochondria the endoplasmic reticulum the plasma membrane
the mitochondria
Homeostatic control of body temperature is termed a) thermic monitoring. b) energetics. c) thermoregulation. d) basal metabolic rate.
thermoregulation.