Test Bank Guyton and Hall Textbook of Medical Physiology 14th Edition Hall

Test Bank Guyton and Hall Textbook of Medical Physiology 14th Edition Hall PREFACE TEST BANK with Complete Questions and Solutions. To clarify, this is the TEST BANK, not the textbook. You get immediate access to download your test bank. You will receive a complete test bank; in other words, all chapters shown in the table of contents in this preview will be there. Test banks come in PDF format; therefore, you do not need specialized software to open them. Chapter 1. Functional Organization of the Human Body and Control of the “Internal Environment” Test Bank 1. The most abundant type of cell in the human body is which of the following? A. Neuron B. Epithelial cell C. Red blood cell D. White blood cell E. Vascular smooth muscle cell F. Skeletal muscle cell ANS: C 2. The most abundant substance in the human body and the approximate percentage of that substance in the body is which of the following? A. Protein, 30% B. Protein, 60% C. Water, 30% D. Water, 60% E. Carbohydrate, 30% F. Carbohydrate, 60% ANS: D 3. A large volume of blood is transfused to a person whose baroreceptor blood pressure control system is not functioning and arterial blood pressure rises from the normal level of 100 to 160 mm Hg. If the same volume of blood is infused into the same person when the baroreceptor system is functioning and this time the arterial pressure increases from the normal level from 100 mm Hg up to 120 mm Hg, calculate the gain of the baroreceptor system in this person. A. -3 B. -2 C. -1 D. 0 1E. +1 F. +2 G. +3 ANS: B 4. Which of the following substances has the highest extracellular fluid to intracellular fluid concentration ratio for most mammalian cells? A. Sodium ions B. Potassium ions C. Carbon dioxide D. Glucose E. Protein ANS: A 5. Exchange of substances between the cardiovascular system and the interstitial fluid occurs mainly in which of the following? A. Arteries B. Arterioles C. Capillaries D. Venules E. Veins ANS: C 6. Which of the following is the approximate distance from the capillaries to most cells of the body? A. Less than 50 angstroms B. Less than 50 microns C. Less than 50 millimeters D. Less than 100 angstroms E. Less than 100 microns F. Less than 100 millimeters ANS: A 7. When a person is at rest, how much time is required for the blood in the circulation to traverse the entire circulatory circuit? A. 1 second B. 1 minute C. 3 minutes D. 4 minutes E. 5 minutes ANS: B 8. feedback is often referred to as a "vicious cycle" because it leads to instability and sometimes death. A. Postitive, progressive 2B. Positive, diminished C. Negative, progressive D. Negative, diminished E. Adaptive, progressive ANS: A 9. Which of the following is an example of positive feedback in the body? A. Clotting of blood B. Return of blood pressure toward normal after a hemorrhage C. Increased respiration rate caused by accumulation of carbon dioxide in the blood D. Decreased sympathetic nervous system activity that occurs in response to increased blood pressure ANS: A Chapter 2. The Cell and Its Functions Test Bank Refer to the following list to answer questions 1-3: A. Nucleolus B. Nucleus C. Agranular endoplasmic reticulum D. Granular endoplasmic reticulum E. Golgi apparatus F. Endosomes G. Peroxisomes H. Lysosomes I. Cytosol Identify the cellular location for each of the following steps involved in the synthesis and packaging of a secreted protein. Initiation of translation. ANS: I Protein sorting and packaging. ANS: E Gene transcription. 3ANS: B 4. Which of the following is true for both pinocytosis and phagocytosis? A. Involves the recruitment of actin filaments B. Occurs spontaneously and non-selectively C. Permits the uptake of bacterium into the cytosol D. Is only observed in macrophages and neutrophils E. Does not require ATP ANS: A 5. The cell membrane is LEAST permeable to which of the following? A. Sodium B. Oxygen C. Ethanol D. Carbon Dioxide E. Water ANS: A 6. The term “glycocalyx” refers to: A. The negatively charged carbohydrate chains that protrude into the cytosol from glycolipids and integral glycoproteins B. The negatively charged carbohydrate layer on the outer cell surface C. The layer of anions aligned on the cytosolic surface of the plasma membrane D. The large glycogen stores found in “fast” muscles E. A mechanism of cell-cell attachment ANS: B 7. Proteins are sorted for their delivery to lysosomes, secretory vesicles and the plasma membrane in the: A. Golgi apparatus B. smooth endoplasmic reticulum C. nucleus D. endocytotic vesicle ANS: A 8. Ubiquinone, an electron acceptor in the electron transport chain (oxidative phosphorylation), is found in the: A. Inner mitochondrial membrane B. Mitochondrial matrix C. Outer mitochondrial membrane D. Nucleus ANS: A 9. The citric acid cycle or Kreb’s cycle, takes place in the: 4A. Mitochondrial matrix B. Inner mitochondrial membrane C. Outer mitochondrial membrane D. Inner mitochondrial space ANS: A 10. Which of the following processes is NOT ATP-dependent? A. Ciliary movement B. Positive chemotaxis C. Movement of carbon dioxide across a lipid bilayer D. Endocytosis E. Smooth muscle contraction ANS: C 11. This cytoskeletal element plays a role in certain forms of cell movement and is an essential component of the mitotic spindle: A. Phospholipids B. Glycocalyx C. F-actin D. Microtubules E. Clathrin ANS: D 12. Lipid synthesis occurs in the: A. Trans-Golgi network B. Granular or “rough” endoplasmic reticulum C. Agranular or “smooth” endoplasmic reticulum D. Nucleus E. Lysosome ANS: C 13. This cytoskeletal element plays a role in certain forms of cell movement and is an essential component of the mitotic spindle: A. Phospholipids B. Glycocalyx C. F-actin D. Microtubules E. Clathrin ANS: D 14. The abnormal cleavage of mannose residues during the post-translational processing of glycoproteins has been shown to result in the development of a lupus-like autoimmune disease in mice. The abnormal cleavage is due to a mutation of the enzyme -mannosidase II. Based on your understanding of the processing of membrane proteins, you would predict this enzyme 5to be localized to the: A. Nucleus B. Cytosol C. Golgi apparatus D. Lysosomes E. Peroxisomes ANS: C 15. The observation that abnormal cleavage of mannose residues from glycoproteins causes an autoimmune disease in mice is most consistent with the role of which of the following structures in the normal immune response? A. Cytoskeleton B. Glycocalyx C. Peroxisomes D. Lysosomes E. Microtubules ANS: B 16. A pure phospholipid bilayer is most permeable to: A. Sodium B. Calcium C. Chloride D. Water E. Oxygen ANS: E Chapter 3. Genetic Control of Protein Synthesis, cell function, and cell reproduction Test Bank 1. Facioscapulohumeral muscular dystrophy (FSHD) is characterized by the deletion of a DNA sequence on chromosome 4q35. This deletion correlates with both the inability of a specific protein complex to bind to the DNA and an overexpression of the genes upstream of the deletion. The sequence deleted in FSHD most likely functions normally as: A. An activator protein B. A repressor protein C. An activator element D. A repressor element E. A promoter sequence ANS: D 2. In comparing two cell types from the same person (e.g. a neuron and an epithelial cell) the variation in their proteomes, or the proteins expressed by each cell type, reflects: A. Differences in the DNA contained in the nucleus of each cell 6B. Variation in the numbers of copies of specific genes in their respective genomes C. Cell-dependent expression and/or repression of specific genes D. Differences in the number of chromosomes in each cell E. The loss of genes from each genome over time ANS: C 3. Which of the following correctly describes the sequence of events that occur during the synthesis and packaging of a secreted protein? A. The gene is transcribed in the cytosol; mRNA is translated by ribosomes bound to “rough” endoplasmic reticulum; the protein is packaged for secretion in the trans- Golgi network B. The gene is transcribed in the nucleus; RNA polymerase binds to the start codon; the protein is packaged for secretion in the trans-Golgi network C. Translation is initiated in the cytosol; the protein is carried in membrane-bound vesicles to the cis- Golgi apparatus; the protein is packaged for secretion in the trans- Golgi network D +. Translation is initiated in the cytosol; new polypeptide is co-transported with across the outer ER membrane; the protein is glycosylated in the Golgi apparatus Na E. Translation is initiated by small ribosomal subunits anchored to the ER membrane; protein is glycosylated in the Golgi apparatus; the protein is packaged into lysosomes ANS: C 4. Which of the following does NOT play a direct role in the process of transcription? A. Helicase B. RNA polymerase C. A chain terminating sequence D. “Activated” RNA molecules E. A promoter sequence ANS: A 5. “Redundancy” or “degeneration” of the genetic code occurs during which of the following steps of protein synthesis? A. DNA replication B. Transcription C. Post-transcriptional modification D. Translation E. Protein glycosylation ANS: B 6. Which of the following bases is NOT present in RNA? A. Cytosine B. Thymine C. Adenine D. Guanine ANS: B 77. The process of translation takes place: A. In the cytosol and on the surface of the “rough” endoplasmic reticulum B. In the nucleus and on the surface of the “rough” endoplasmic reticulum C. In the cytosol and the trans-Golgi network (TGN) D. In the nucleus and on the outer mitochondrial membrane ANS: A 8. Which of the following statements about translation is NOT true? A. Multiple ribosomes can simultaneously translate a single mRNA molecule B. Each codon codes for one amino acid C. One mRNA molecule can code for multiple proteins, depending on which start codon is recognized by the small ribosomal subunit D. Translation is terminated when the release factor binds to the stop codon ANS: C 9. The following statements accurately describe the process of DNA replication EXCEPT: A. The entire genome is replicated only once per cell cycle B. It occurs during the M phase of the cell cycle C. Nucleotides are incorporated into the growing DNA strand at the 3’ end D. DNA “proofreading” is performed by DNA polymerase ANS: C 10. The mechanism by which allolactose regulates the transcription of the beta- galactosidase gene is best described as: A. De-repression B. Repression C. Activation D. Negative feedback E. Positive feedback ANS: A 11. Which of the following does NOT occur during the process of mitosis? A. Replication of the genome B. Condensation of the chromosomes C. Fragmentation of the nuclear envelope D. Alignment of the chromatids along the equatorial plate E. Separation of the chromatids into two sets of 46 “daughter” chromosomes ANS: A 12. “Redundancy” or “degeneration” of the genetic code occurs during which of the following steps of protein synthesis: A. DNA replication B. Transcription C. Post-transcriptional modification D. Translation E. Protein glycosylation ANS: B 13. The appearance of which of the following distinguishes eukaryotic cells from lower units of life like bacteria and viruses? 8A. DNA B. RNA C. Membranes D. Protein E. Nucleus ANS: E Chapter 4. Transport of Substances Through Cell Membranes Test Bank 1. An artificial membrane is created consisting of a lipid bilayer without protein molecules in the membrane. The lipid composition of the membrane is essentially the same as that of a normal, biological membrane. Which of the following substances permeates the membrane more readily than water molecules? A. Carbon Dioxide B. Glucose C. Glycerol D. Sodium E. Urea ANS: A 2. A cell is equilibrated in an aqueous solution of 300 mOsm/L sodium chloride. Which of the following best describes what will happen to cell volume when the cell is placed in an aqueous solution of 300 mOsm/L calcium chloride? A. Decrease B. Decrease and then increase C. Increase D. Increase and then decrease E. No change ANS: E -4 3. The intracellular calcium ion concentration of ventricular muscle cells averages 10 mmol/L during diastole. The calcium ion concentration in transverse tubules (T-tubules) averages 2.5 mmol/L at rest. A protein transporter on the membrane of the T-tubule exchanges sodium for calcium. The transporter uses the transmembrane sodium gradient to fuel the exchange. Which of the following transport mechanisms best describes this type of transporter? A. Facilitated diffusion B. Primary active transport C. Secondary active co-transport D. Secondary active counter-transport E. Simple diffusion ANS: D 94. Human red blood cells (RBCs) and rabbit RBCs are equilibrated in separate solutions of isotonic saline (300 mOsm/L NaCl). The human RBCs are then placed in a solution of 300 mOsm/L glycerol, which causes them to swell and burst. However, rabbit RBCs placed in 300 mOsm/L glycerol neither swell nor shrink. Based on this information, which of the following can be concluded about a 300 mOsm/L solution of glycerol for the different cell types? Human RBCs Rabbit RBCs A. Hypertonic and hyperosmotic B. Hypotonic and hypoosmotic C. Hypotonic and isoosmotic D. Isotonic and hypoosmotic E. Isotonic and isoosmotic F. Isotonic and hyperosmotic ANS: C 5. The molarity of a 2% solution of NaCl is 340 mmol/L. The molecular weight of NaCl is 58.5. What is the osmolarity of a 2% solution of NaCl (in mOsm/L)? A. 170 B. 340 C. 510 D. 680 ANS: D 6. Secondary active transport typically moves which of the following substances against a concentration gradient? Glucose Amino acids A. No B. No C. Yes D. Yes E. Yes ANS: D 7. Which of the following transport mechanisms can move sodium ions across a cell membrane? Primary active Secondary active Simple transport transport diffusion No No Yes Yes Yes ANS: E 8. The diagram illustrates possible changes in red blood cell volume resulting from a change in extracellular fluid composition for a cell equilibrated in a 150 mmol/L solution of sodium chloride (NaCl) at time zero. Which curve best illustrates the volume change caused by immersion of the cell in an aqueous solution of 300 mOsm/L calcium chloride (CaCl2)? 10 No Yes No Yes Yes No Yes Yes No Yes No No No Yes Yes Sodium ions No Yes Yes No Yes Hypotonic and hypoosmotic Hypertonic and hyperosmotic Isotonic and isoosmotic Isotonic and hyperosmotic Hypotonic and isoosmotic Isotonic and isoosmoticANS: C 9. The diagram illustrates possible changes in red blood cell volume resulting from a change in extracellular fluid composition for a cell equilibrated in a 150 mmol/L solution of sodium chloride (NaCl) at time zero. Which curve best illustrates the volume change caused by immersion of the cell in an aqueous solution of 200 mOsm/L NaCl and 200 mOsm/L glycerol? ANS: B 10. Which of the following pairs of aqueous solutions will exert equal osmotic pressures across a normal cell membrane after steady-state conditions have been established? Solution A Solution B A. 10% albumin B. 100 mmol/L NaCl C. 300 mOsm/L glucose D. 300 mOsm/L glycerol 300 mOsm/L glycerol E. ANS: E 11. Two compartments (X and Y) are separated by a typical biological membrane (i.e., lipid bilayer). The concentrations of a permeant solute (i.e., urea) at time zero are shown. Which of the drawings below represents the volumes of X and Y when the system reaches equilibrium? 10% IgG 200 mmol/L CaCl2 300 mOsm/L urea 300 mOsm/L NaCl 300 mOsm/L urea ANS: A 12. The diagram illustrates possible changes in red blood cell volume resulting from a change in extracellular fluid composition for a cell equilibrated in 150 mmol/L NaCl at time zero. Which curve best illustrates the volume caused by immersion of the cell in an aqueous solution of 150 mmol/L CaCl2? ANS: E 13. Two compartments (X and Y) are separated by a typical biological membrane (lipid bilayer). The concentrations of a non-permeant molecule (glucose) at time zero are shown. Which of the drawings below represents the volumes of X and Y when the system reaches equilibrium? 11ANS: B 14. The diagram shows a model cell that transports substance X across the cell membrane. The cell is equipped with a Na-K-ATPase pump as shown. Substance X enters the cell by a coupled transport mechanism and exits the cell by carrier-mediated diffusion. Treatment with a substance that inhibits the Na-K-ATPase pump inhibits the transport of X by which of the following mechanisms? A +. Decreasing intracellular K concentration B. + C. + Decreasing intracellular Increasing intracellular D +. Increasing intracellular concentration ANS: D 15. The diagram shows a bag (with permeability characteristics similar to that of a normal cell) that contains a 100 mM solution of urea at time zero. The bag is placed in a beaker containing 100 mM glucose. Which of the following best describes the tonicity and osmolarity of the glucose solution as well as any changes in bag volume (assume that the bag volume is infinitely small compared to beaker volume)? Osmolarity Tonicity A. Hyperosmotic Hypertonic B. Hyperosmotic Hypotonic C. Hyperosmotic Isotonic D. Hypoosmotic Hypotonic E. Hypoosmotic Isotonic F. Hypoosmotic Hypertonic G. Isoosmotic H. Isoosmotic Isoosmotic I. ANS: G Hypertonic Hypotonic Isotonic Bag volume Decreases Increases No change Decreases Increases No change Decreases Increases No change Na Na K concentration concentration Chapter 5. Membrane Potentials and Action Potentials 12Test Bank 1. The diagram shows compound action potentials recorded percutaneously from a single site a certain distance from a stimulating electrode indicated by the arrow. Which peak is most likely to represent action potentials from small, non-myelinated motor neurons? ANS: D 2. A 42-year-old woman decides to lose weight on a diet prescribed by an anorexic friend. She loses about 30 pounds in 45 days, but her serum potassium level falls to 2.1 mmol/L (normal: 3.5 to 5.0 mmol/L). Which of the following changes is most likely to occur in this young woman? A. Depolarization of the resting membrane potential B. Hyperpolarization of the resting membrane potential C. Increased intracellular potassium concentration D. Potassium equilibrium potential becomes less negative ANS: B 3. An 22-year-old man is admitted to the emergency department after an automobile accident. He has not lost a large amount of blood, but he suffers from a severe crush injury to his right leg. He is conscious and exhibits flaccid paralysis. Electrocardiogram results show a shortened QT interval and an increase in the P-R interval (i.e., decreased duration of action potential and decreased conduction velocity). Laboratory results indicate that his serum potassium level has increased to a value of 6.5 mEq/L (normal: 3.5 to 5.0 mEq/L). This increase in serum potassium causes which of the following? A. A decreased net driving force for potassium from cells B. Decreased intracellular potassium concentration C. Hyperpolarization of the resting membrane potential D. More negative Nernst potential for potassium E. More negative resting membrane potential ANS: A 4. An 88-year-old nursing home resident has diabetes mellitus and is taking diuretics for hypertension. His blood glucose concentration has recently been greater than 350 mg/dL. He is disoriented and has had limited oral intake for about five days. His vital signs include a temperature of 100.5°F, a supine blood pressure and pulse of 150/90 mm Hg and 100 beats per minute, and an upright blood pressure and pulse of 130/88 mm Hg and 118 beats per minute. The findings on examination of the heart are normal, and his axillae + ar +e dry. The table shows serum Na and K values before and after the dehydration that has occurred in this patient. The resting membrane potential of a cardiac myocyte was about −70 millivolts before dehydration occurred. What is the resting membrane potential of a cardiac myocyte after dehydration occurred, assuming no change in membrane 13+ c +onductance or intracellular concentrations of Na K or ions? A. −100 millivolts B. −50 millivolts C. −60 millivolts D. −70 millivolts E. −90 millivolts ANS: D 5. A 44-year-old man is recovering from third degree burns over 50% of his body surface area. His serum potassium level is low (2.9 mEq/L). He exhibits postural hy +potension and skeletal muscle weakness. If the equilibrium potential for ne +uron is 105 mV and the equilibrium potential for − K in a Na is +55 mV, what would be an approximate value for the resting membrane potential for a neuron in this man? A. +20 mV B. +48 mV C. +80 mV D. −25 mV E. −48 mV F. −96 mV ANS: F 6. A 23-year-old man receives a crush injury to his right leg in an automobile accident. + His serum potassium level is 6.4 mEq/L. The equilibrium potential for K in a + motoneuron is −73 mV, and the equilibrium potential for Na is +59 mV. Which of the following best describes the resting membrane potential (in mV) for a typical motoneuron in this man? A. +62 B. +90 C. −13 D. −67 E. −84 ANS: D 7. A 56-year-old woman is referred to the neurology clinic for evaluation of her long- term problem of a stumbling gait and a tendency to fall. Her visual acuity also seems to change periodically. Neurological findings suggest multiple sclerosis. This diagnosis is further supported by magnetic resonance imaging, which shows of areas of demyelination in the central nervous system. Other tests show the presence of oligoclonal bands in the spinal fluid. The loss of myelin from a nerve fiber has which of the following effects? A. Decreased conduction velocity of action potential or no action potential B. Decreased energy requirement for successful action potentials C. Increased conduction velocity of action potential D. Increased velocity of salutatory conduction ANS: A 148. The diagram shows an action potential for a nerve fiber. What is the threshold potential for this neuron? A. −15 mV B. −50 to −60 mV C. −60 to −70 mV D. −70 to −80 mV E. −80 mV ANS: C 9. In the diagram shown, Em represents the measured initial membrane potential for a hypothetical cell in vivo. In relation to this membrane potential, the equilibrium potentials of three ions (X, Y, Z) are represented. Pick the path most likely taken by the membrane potential when membrane conductance for ion Y is increased. ANS: B 10. In the diagram shown, Pmemb represents the initial membrane potential for a hypothetical cell. In relation to this membrane potential, the equilibrium potentials of three ions (Q, R, S) are represented. Pick the path most likely taken by the membrane potential when membrane conductance for ion Q and ion S are increased simultaneously by 1000-fold. ANS: C 11. The diagram shows compound action potentials recorded percutaneously from a single site at a certain distance from a stimulating electrode (S) indicated by the ARROW. What can be concluded from the diagram concerning action potential velocity for the various categories of neurons? A. W = X = Y = Z B. W > X > Y > Z C. W > Y > X D. Y > W > Z E. Z > Y > X > W ANS: B 12. Five hypothetical neurons are shown below. Neurons A and B are myelinated, whereas neurons C, D, and E are not myelinated. Which neuron is most likely to have the fastest conduction velocity? 15A. B. C. D. E. ANS: B 13. In the following graph, Em represents the measured initial membrane potential for a hypothetical cell in vivo. In relation to this membrane potential, the equilibrium potentials of three ions (Q, R, S) are represented. During resting conditions, the conductance for Q and S ions is the same, which is 1000 times greater than that of ion R. Pick the path most likely taken by the membrane potential when membrane conductance to ion Q is 2 decreased to 0 mmho/cm . ANS: D 14. A 63-year-old man is dehydrated after three days of alcohol abuse. His serum sodium level has increased from a normal value of 140 mEq/L to 147 mEq/L. The resting membrane potential of a typical neuron was −80 mV before dehydration. What is the most likely resting membrane potential of a typical neuron after the dehydration, assuming no change in resting sodium conductance? A. −72 mV B. −74 mV C. −80 mV D. −88 mV E. −98 mV ANS: C 15. A 24-year-old soldier suffers a burn injury over 60% of his body surface area, which le +ads to a decrease in the serum K concentration from a normal value of 4 mEq/L to a value of 2.5 mEq/L. Which of the following sets of changes best describe the resting me +mbrane potential and the K Nernst potential in a cardiac myocyte after the injury? R +esting membrane potential K Nernst potential 16A. Less negative B. Less negative C. More negative D. More negative E. No change Less negative More negative Less negative More negative No change ANS: D 16. The diagram shows an action potential for a nerve fiber. Use the diagram to answer the question. Where on the curve does potassium conductance exceed sodium conductance? A. V and Z B. V, W, and X C. V, X, and Z D. W, X, and Y E. X, Y, and Z ANS: A 17. Consider the action potential shown. Which of the following changes in membrane + c +onductances for Ca (assume normal K and best account for the prolonged plateau conductances for both ions during resting conditions, i.e., only the changes in conductances are important)? A. B. C. D. ANS: A 18. A neuron from an extraterrestrial being has the intracellular and extracellular sodium and potassium concentrations shown in the table (in mM). During resting conditions, the sodium conductance is 100- fold greater compared to the potassium conductance. Which of the following (in mV) best describes the resting membrane potential (Vm) in this alien neuron (assume that Vm is dictated mainly by sodium and potassium conductances and that the Nernst equation applies)? A. +150 B. +55 C. 0 D. −55 17E. −150 ANS: B 19. The intracellular concentration of ion Z is 100 milliequivalents per liter (mEq/L), and the extracellular concentration is 5 mEq/L. The molecular weight of molecule Z is ~40 daltons. This relatively high intracellular concentration of molecule Z is best explained by which of the following? A. Exocytosis B. Extracellular assembly C. Facilitative diffusion D. Intracellular production E. Primary active transport F. Simple diffusion ANS: E 20. Equilibrium potentials for Na, K, and Cl are shown. Assume that a cell is permeable to all three ions and has a resting membrane potential of −85 mV. Which of the following best describes the net movement of the various ions across the cell membrane by way of passive diffusion? Sodium Potassium A. Inward B. Inward C. Inward D. Inward E. Outward F. Outward G. Outward H. Outward ANS: D Chapter 6. Contraction of Skeletal Muscle Test Bank 1. A 28-year-old man has been training as a distance runner for the past six years. Compared with a sprinter, which of the following is decreased in the skeletal muscles of this athlete during resting conditions? A. Capillary density B. Glycolytic enzyme content C. Mitochondrial volume density D. Myoglobin content E. Oxidative capacity ANS: A 18 Inward Inward Outward Outward Inward Inward Outward Outward Chloride Inward Outward Inward Outward Inward Outward Inward Outward2. A physiology experiment is conducted in which a skeletal muscle twitch is initiated using an electrical stimulator. Which factor contributes to the termination of a typical skeletal muscle twitch? A. Calcium uptake by sarcoplasmic reticulum B. Closure of transverse tubules C. Depletion of calcium stores from sarcoplasmic reticulum D. Exhaustion of muscle ATP stores E. Stimulation of dihydropyridine (DHP) receptors ANS: A 3. A 24-year-old medical student goes to the local gym to lift weights. She begins by bench- pressing 100 pounds as a warm-up procedure and then gradually increases the weight. Which of the following occurs as she adds more weight? A. Decreased frequency of motor nerve action potentials B. Decreased velocity of motor nerve action potentials C. Increased frequency of motor nerve action potentials D. Increased velocity of motor nerve action potential E. Involvement of fewer motor units ANS: C 4. A 24-year-old woman is admitted to the emergency department after an automobile accident in which lacerations to the left wrist severed a major tendon. The severed ends of the tendon were overlapped by 6 cm to facilitate suturing and reattachment. Which of the following characteristics would be expected after six weeks compared with the pre- injured muscle? Assume that series growth of sarcomeres cannot be completed within six weeks. Passive tension A. Decrease B. Decrease C. Increase D. Increase E. No change ANS: D 5. During the contraction of a skeletal muscle fiber, the actin and myosin filaments slide past each other. Which of the following represent expected changes in the widths of I- bands and A-bands during the contraction process? I-band width A-band width A. B. C. D. E. ANS: D 6. When a person lifts a 25-pound weight, what type or types of muscle contraction are involved? Isometric contraction only Isotonic 19 ↑ ↓ ↓ ↓ ↔ ↔ ↑ ↓ ↔ ↑ Maximal active tension Decrease Increase Increase Decrease No changecontraction only Isometric contraction followed by isotonic contraction Isotonic contraction followed by isometric contraction ANS: C 7. The length-tension diagram shown was obtained from a skeletal muscle with equal numbers of red and white fibers. Supramaximal tetanic stimuli were used to initiate an isometric contraction at each muscle length studied. The resting length was 20 cm. What is the maximum amount of active tension this muscle is capable of generating at a preload of 100 grams? A. 145 to 155 grams B. 25 to 35 grams C. 55 to 65 grams D. 95 to105 grams E. Cannot be determined ANS: C 8. The diagram shows the relationship between muscle tension and sarcomere length for muscle. Which point on the curve represents tension development at a normal resting length for skeletal muscle? ANS: C 9. The diagram shows the relationship between muscle tension and sarcomere length for muscle. Which point on the curve represents tension development at a normal resting length for cardiac muscle? ANS: B 10. A 29-year-old woman has been training as a distance runner for the past five years. Which set of changes best describes the skeletal muscles of this woman compared with a sprinter? Capillary density Oxidative capacity Myoglobin content Fiber diameter 20A. B. C. D. E. ANS: D 11. The length-tension diagram shown on the right was obtained from a skeletal muscle with equal numbers of red and white fibers. Supramaximal tetanic stimuli were used to initiate an isometric contraction at each muscle length studied. What are the values in grams of preload, active tension, and total tension when the muscle length is 60 cm? A. B. C. D. E. ANS: A 12. A 45-year-old man goes to the local gym to lift weights. He begins by bench-pressing 130 pounds as a warm-up procedure and then gradually increases the weight. Which of the following sets of changes occur as he adds more weight? Activation of motor units Frequency of motor nerve action potentials A. B. C. D. E. F. ANS: E Decreased Decreased Decreased Increased Increased Increased Decreased Increased No change Decreased Increased No change Preload 100 100 150 200 200 Active tension 200 300 250 100 200 Total tension 300 200 300 300 300 Decreased Decreased Increased Increased Increased Decreased Decreased Increased Increased Increased Decreased Increased Decreased Increased Increased Decreased Increased Decreased Decreased Increased 13. The skeletal muscle sarcomere normally has a narrow range of lengths in vivo, but sarcomere length can vary greatly in vitro under non-physiological conditions. The diagram shows sarcomeres at various lengths. At which length can the sarcomere exert its maximum force during an isometric contraction? 21A. 1.6 µm B. 2.1 µm C. 2.8 µm D. 3.0 µm E. 3.5 µm ANS: B 14. The diagram shows the relationship between contraction velocity and force. Which of the following muscles is most likely to correspond to muscle number 1 shown on the diagram (assume that all muscles shown are at their normal resting lengths). A. B. C. D. E. ANS: E 15. The diagram shows the relationship between contraction velocity and force. Which of the following muscles is most likely to correspond to muscle number 2 shown on the diagram (assume that all muscles shown are at their normal resting lengths)? A. B. C. D. E. ANS: D 2216. The diagram shows force-velocity relationships for three different skeletal muscles. Which of the following curves most likely correspond to glycolytic, oxidative, and mixed muscle types? Glycolytic Oxidative A. X B. X C. Y D. Y E. Z F. Z ANS: B 17. The dark color of red skeletal muscle (slow twitch muscle) can be attributed to a relative abundance of which of the following compared to white skeletal muscle (fast twitch muscle)? A. Blood capillaries B. Mitochondria C. Myoglobin D. Myosin ATPase E. Oxidative enzymes ANS: C Y Z X Z X Y Mixed Z Y Z X Y X Chapter 7. Excitation of Skeletal Muscle: Neuromuscular Transmission and Excitation-Contraction Coupling Test Bank 1. A 45-year-old man has botulinum toxin (Botox®) injections in the frontalis muscles. Which of the following sets of changes are most likely to occur in the treated muscles with repeated injections over a period of ten years? Fiber diameter Fiber number A. decreased B. decreased C. decreased D. increased E. increased F. increased ANS: A 2. Which of the following represents the correct temporal order of events for skeletal muscle? First Second A. End plate potential B. End plate potential Muscle action potential Nerve action potential Third Nerve action potential Muscle action potential 23 decreased decreased increased decreased decreased increased Contraction velocity decreased increased increased decreased increased increasedC. Muscle action potential D. Muscle action potential E. Nerve action potential F. Nerve action potential ANS: E 3. Myasthenia gravis is an autoimmune disease in which antibodies damage which of the following? Acetylcholine Ligand-gated channels on postsynaptic membrane Ligand-gated channels on presynaptic membrane Voltage- gated channels on postsynaptic membrane Voltage-gated channels on presynaptic membrane ANS: B 4. Lambert-Eaton myasthenic syndrome is an autoimmune disease in which antibodies damage which of the following? A. Acetylcholine B. Ligand-gated channels on postsynaptic membrane C. Ligand-gated channels on presynaptic membrane D. Voltage-gated channels on postsynaptic membrane E. Voltage-gated channels on presynaptic membrane ANS: E 5. A 59-year-old college professor visits his physician because of muscle fatigue that worsens later in the day. The physician notices that the man has droopy eyelids and seems to have an overall weakness in his muscles. After the intravenous administration of Tensilon®, which blocks degradation of acetylcholine, the droopy eyelids and symptoms of muscle weakness appear to subside. Which of the following best describes the patient’s condition? A. Encephalitis B. Fibromyalgia C. Flaccid paralysis D. Myasthenia gravis E. Poliomyelitis ANS: D 6. A 3-year-old child is admitted to the emergency department of University Hospital. The child exhibits extreme salivation, lacrimation, tremors, and tachycardia. The slight erythema and mild edema found on the child's hand suggest a spider bite. The mother acknowledges that the child has a fascination with spiders and has seen black widow spiders in the yard. The neurotoxic venom of the black widow spider (i.e., latrotoxin or latrophilin) can increase the flux of calcium ions into the presynaptic terminal. What is the likely outcome of a black widow spider bite? A. Decreased acetylcholine release from nerve terminals B. Hyperpolarization of postsynaptic membranes C. Hyperpolarization of presynaptic membranes D. Increased acetylcholine release from nerve terminals 24 End plate potential Nerve action potential End plate potential Muscle action potential Nerve action potential End plate potential Muscle action potential End plate potentialE. Inhibition of acetylcholinesterase ANS: D 7. An apparently healthy 12-year-old boy dies during a minor surgical procedure while under general anesthesia. An uncle had also died during a surgical procedure. Results of a halothane contracture test indicate that the child had malignant hyperthermia (MH). The MH crisis is associated with which of the following? A. Decreased anaerobic metabolism B. Decreased CO2 production by muscles C. Decreased lactic acid production by muscles D. Defective ryanodine receptors E. Decreased usage of ATP in muscles ANS: D 8. Skeletal muscle and cardiac muscle contract when calcium binds to which structure or molecule? Active sites Calmodulin Myosin head Tropomyosin Troponin-C ANS: E 9. Which of the following represents the correct temporal order of events for skeletal muscle? First Second Muscle action potential Muscle action potential Muscle contraction Muscle contraction Nerve action potential action potential ANS: E 10. Binding of calcium to which structure or molecule initiates a contraction in smooth muscle, skeletal muscle, and cardiac muscle? Smooth muscle Skeletal muscle A. Active sites B. Active sites C. Calmodulin D. Calmodulin E. Myosin heads F. Myosin heads Calmodulin Troponin Tropomyosin Troponin Tropomyosin Troponin Cardiac muscle Troponin Calmodulin Active sites Troponin Troponin Tropomyosin ANS: D 11. A 23-year-old man loses consciousness while driving, hits a tree, and dies within 15 minutes. The 25 Muscle contraction Nerve action potential Muscle action potential Nerve action potential Muscle action potential Muscle contraction Third Nerve action potential Muscle contraction Nerve action potential Muscle action potential Muscle contraction Nerve Muscle action potentialpolice find his stiff body five hours later. Rigor mortis is caused by a decrease in which of the following? A. Acetylcholine B. Actin-myosin cross-bridges C. Myoplasmic calcium levels D. Interstitial lactate levels E. Muscle ATP levels ANS: E 12. A father and his 10-year-old daughter died suddenly of suffocation after ingesting smoked whitefish chubs from the Great Lakes. Three other family members are sick, complaining of dry mouths despite drinking copious amounts of fluids. Their upper eyelids droop. Their vision is clear, but their pupils are wide and do not narrow when a light is flashed. Two of them require artificial respiration. The suspect is botulism (Clostridium botulinum). The surviving patients begin improving soon after receiving the only treatment available, E antitoxin. The deadly effect of botulinum toxin results from which of the following? A. Decreased release of acetylcholine B. Decreased release of norepinephrine C. Depletion of muscle calcium stores D. Skeletal muscle tetany E. Stimulation of ryanodine receptors ANS: A 13. Which of the following best describes the dynamics of calcium release and calcium uptake during the development of frequency-induced muscle tetany? A. Release from longitudinal tubules exceeds uptake by terminal cisternae B. Release from longitudinal tubules exceeds uptake by T-tubules C. Release from terminal cisternae exceeds uptake by longitudinal tubules D. Release from terminal cisternae exceeds uptake by T-tubules E. Release from T-tubules exceeds uptake by longitudinal tubules F. Release from T-tubules exceeds uptake by terminal cisternae ANS: C 14. Which of the following best describes the correct temporal order of events for the opening of nicotinic acetylcholine (nACh) channels on the muscle membrane, the opening of voltage-gated sodium channels on the muscle membrane, and initiation of presynaptic action potentials (AP)? First Second A. nACh channels B. nACh channels C. Presynaptic AP D. Presynaptic AP E. Voltage gated Na channels F. Voltage gated Na channels ANS: C Presynaptic AP Voltage gated Na channels nACh channels Voltage gated Na channels nACh channels nACh channels Third Voltage gated Na channels Presynaptic AP Voltage gated Na channels nACh channels Presynaptic AP Presynaptic AP 26Chapter 8. Excitation and Contraction of Smooth Muscle Test Bank 1. The contraction of smooth muscle can be attenuated even when intracellular calcium levels are high. This unique ability of smooth muscle can be attributed to variations in the activity of which of the following? A. Actin B. Adenosine triphosphate (ATP) C. Calcium-calmodulin complex D. Calmodulin E. Myosin light chain phosphatase ANS: E 2. Multiple elements can regulate the contraction of smooth muscle, including endocrine, neurocrine, and paracrine factors. This level of diversity in the control of smooth muscle contraction can be attributed to a diversity of which of the following? A. Actin-myosin arrangement B. Calcium sensitivities C. Cell-surface receptors D. Motor end plates E. Subneural cleft architecture ANS: C 3. The effect of autonomic nerve stimulation on smooth muscle contractile behavior depends on the types of receptors on the smooth muscle fibers. Which of the following best describes the effects of acetylcholine and norepinephrine on various types of smooth muscle? Acetylcholine Norepinephrine A. Contraction only B. Contraction only C. Relaxation only D. Relaxation only E. Relaxation or contraction F. Relaxation or contraction ANS: F 4. Unlike skeletal muscle, the contraction of smooth muscle requires which of the following? A. Activation of ryanodine receptors B. Phosphorylation of myosin light chains C. The presence of intracellular calcium D. Troponin binding of calcium E. Voltage activation of dihydropyridine receptors ANS: B 5. Which of the following factors are important for initiating smooth muscle contractions? 27 Relaxation or contraction Relaxation only Contraction only Relaxation only Contraction only Relaxation or contractionHormones A. No B. No C. Yes D. Yes E. Yes ANS: E 6. The sensitivity of the smooth muscle contractile apparatus to calcium can increase. This increase in calcium sensitivity can be attributed to a decrease in the levels of which of the following substances? A. Actin B. Adenosine triphosphate (ATP) C. Calcium-calmodulin complex D. Calmodulin E. Myosin light chain phosphatase ANS: E 7. Which of the following is the correct temporal order of events for the smooth muscle? A. Myosin light chain (MLC) dephosphorylation, contraction, relaxation, MLC phosphorylation B. MLC dephosphorylation, contraction, MLC phosphorylation, relaxation C. MLC dephosphorylation, relaxation, MLC phosphorylation, relaxation D. MLC phosphorylation, contraction, MLC dephosphorylation, relaxation E. MLC phosphorylation, contraction, relaxation, MLC dephosphorylation F. MLC phosphorylation, MLC dephosphorylation, contraction, relaxation ANS: D Paracrine factors No No No Yes Yes Autonomic nervous system No Yes Yes No Yes Chapter 9. Cardiac Muscle; The Heart as a Pump and Function of the Heart Valves Questions 1-3: A fifty-year-old man has a body weight of 110 kg, resting heart rate is 90 beats/minute, arterial pressure is 120/70 mmHg, arterial hematocrit is 35% and body temperature is normal. His pressure-volume diagram of the left ventricle is shown below. 1. What is his resting cardiac output in ml/minute? A. 900 B. 8,000 C. 9,000 D. 10,000 E. 15,000 ANS: C 282. What event occurs at point D in the man’s pressure-volume relationship? A. A-V valves close B. Aortic valve opens C. Aortic valve closes D. A-V valves open E. Third heart sound ANS: C 3. What is his ventricular ejection fraction? A. 33% B. 50% C. 60% D. 67% E. 80% ANS: D 4. Which of the following will result in spastic contraction of the heart? A. Excess calcium ions in the blood B. Excess potassium ions in the blood C. Excess sodium ions in the blood D. Decreased sympathetic stimulation E. Decreased norepinephrine concentration in the blood ANS: A Questions 5-7: A sixty-year-old woman has a body weight of 110 kg, resting cardiac output is 9,000 ml/minute, arterial pressure is 90/50 mmHg, arterial hematocrit is 25% and body temperature is normal. Her pressure- volume diagram of the left ventricle is shown below. 5. What is her resting heart rate in beats/minute? A. 70 B. 80 C. 90 D. 100 E. 110 ANS: C 6. What event occurs at point A in the woman’s pressure-volume relationship? A. A-V valves close B. Aortic valve opens C. Aortic valve closes D. A-V valves open E. Third heart sound ANS: D 7. If the woman is given a 500 ml whole blood transfusion over a 15 minute period, her ventricular preload will increase. One minute after the transfusion is complete, what will the new stroke volume be assuming her heart is normal? 29A. 70 ml B. 80 ml C. 90 ml D. 100 ml E. 120 ml ANS: A Questions 8-9: A fifty-year-old man has a body weight of 110 kg, resting heart rate is 90 beats/minute, arterial pressure is 120/70 mmHg, arterial hematocrit is 35% and body temperature is normal. His pressure-volume diagram of the left ventricle is shown below. 8. When does the third heart sound occur in the ventricular pressure-volume relationship? A. At point D B. Between point A and point B C. Between point B and point C D. Between point C and point D E. Between point D and point A ANS: B 9. When does the second heart sound occur in the ventricular pressure-volume relationship? A. At point D B. Between point A and point B C. Between point B and point C D. Between point C and point D E. Between point D and point A ANS: A Chapter 10. Rhythmical Excitation of the Heart Test Bank 1. If the sinus node stops discharging, what is the expected heart rate (in beats/minute) if the A-V node takes over as the cardiac pacemaker? A. 15 B. 20 C. 35 D. 50 E. 72 ANS: D 302. If the S-A node discharges at 0.00 seconds, when will the action potential normally arrive at the A-V node? A. 0.03 seconds B. 0.09 seconds C. 0.12 seconds D. 0.16 seconds E. 0.80 seconds ANS: A 3. Which of the following conditions at the S-A node will cause a decrease in heart rate? A. Increased sodium permeability B. Decreased acetylcholine levels C. Increased norepinephrine levels D. Increased potassium permeability E. Increased calcium permeability ANS: