physiology part 2 final
3. The proximal tubule of the nephron is the primary location for the reabsorption of which of the following blood filtrates? a. Sodium b. Proteins c. Glucose d. All of the above
d. All of the above
At the instant following the second heart sound, which heart valves are open? a. Both atrioventricular valves and semilunar valves b. Semilunar valves only c. Atrioventricular valves only d. All valves are closed
d. All valves are closed
How many mL is the tidal volume?How many mL is the tidal volume?
600
How many mL is the expiratory reserve volume?
1700
At an altitude where atmospheric pressure is 500 mm Hg, what is the partial pressure of oxygen? a. 105 mmHg b. 100 mmHg c. 800 mmHg d. 630 mmHg e. 760 mmHg
a. 105 mmHg.
In the normal cardiac cycle, systole is marked by the contraction of myocardial fibers. An influx of which of the following ions across the sarcolemmal membrane is most likely to initiate systolic contraction? a. Ca++ b. Cl- c. HCO3- d. K+ e. Na+
a. Ca++.
In an experiment, vagus nerve stimulation is followed by a decrease in the heart rate and a decrease in myocardial fiber contractility of a normal heart. Which of the following ionic fluxes is most likely responsible for this observed effect? a. Calcium efflux b. Potassium efflux c. Sodium efflux d. Calcium influx e. Sodium influx
a. Calcium efflux
A 68-year-old man has experienced increased sputum production for the past 2 years, along with increasing dyspnea. On examination he has pitting edema to the knees. A chest radiograph shows a prominent right heart border and bilateral pleural effusions. Which of the following pulmonary abnormalities is he most likely to have? a. Decreased compliance b. Decreased PaCO2 c. Increased FEV1 d. Increased functional residual capacity e. Abnormal ventilation perfusion scan
a. Decreased compliance.
A 58-year-old woman goes on a trek to Nepal. After leaving Khatmandu, the group of trekkers ascends to their first camp at 5000 meters in elevation. During the ascent she develops a headache with nausea, but no respiratory distress. Vital signs at camp show her temperature is 36.9°C, pulse 90/min, respiratory rate 23/min, and blood pressure 125/85 mm Hg. Over the next 2 days her headache subsides. Which of the following laboratory test findings is most likely to have occurred in this woman to lessen her symptoms? a. Decreased plasma bicarbonate b. Decreased plasma chloride c. Decreased plasma vasopressin d. Increased PaCO2 e. Increased PaO2
a. Decreased plasma bicarbonate.
Curare is a naturally-occurring compound that competitively binds to nicotinic acetylcholine receptors on muscle cells. Which of the following symptoms might be seen in a patient who has been exposed to curare? a. Diaphragmatic paralysis b. Cardiac arrest c. Excessive salivation d. Muscle spasticity
a. Diaphragmatic paralysis
Which of the following best describes a chemoreceptor response to PO 2 ? a. Peripheral chemoreceptors respond to small changes in PO 2 . b. Peripheral chemoreceptors respond to oxyhemoglobin. c. Central chemoreceptors do not respond to changes in PO 2 . d. Central chemoreceptors respond to only large decreases in PO 2 . e. Peripheral chemoreceptors respond only indirectly to PO 2 .
a. Peripheral chemoreceptors respond to small changes in PO2.
A nurse is examining a patient who has muscle pain and fatigue after working out. He determines that the patient has muscle strain. This is generally caused by which of the following? a. The actin and myosin filaments have been pulled past their ability to overlap b. There is damage to ligamentous attachments c. Excessive contraction causes tetany in the muscle body d. Hypertrophy is causing swelling of the muscle fiber
a. The actin and myosin filaments have been pulled past their ability to overlap
15. Which of the following has a rate of urinary excretion (units of solute per unit time) that is always much lower than its rate of glomerular filtration in a healthy adult? a. Urea b. Potassium c. Sodium d. Glucose
a. Urea.
Vasoconstriction of the efferent arterioles would result in: a. an increase in filtration rate b. a decrease in filtration rate c. a decrease in filtration membrane permeability d. no change in renal function
a. an increase in filtration rate.
Hyperventilation will cause changes in PCO 2 that are detected by the chemoreceptors which causes a(n): a. increase in breathing rate and depth of breathing. b. decrease in breathing rate and depth of breathing. c. increase in depth of breathing only. d. decrease in breathing rate only. e. increase in breathing rate only.
a. increase in breathing rate and depth of breathing.
Creatine a. is reabsorbed in the proximal convoluted tubule by secondary active transport. b. is reabsorbed in the proximal convoluted tubule by diffusion c. is reabsorbed in the distal convoluted tubule by primary active transport. d. is not reabsorbed because the tubule membrane is not permeable to creatine.
a. is reabsorbed in the proximal convoluted tubule by secondary active transport.
The ________ is the respiratory center that appears to facilitate the transition between inspiration and expiration. a. pontine respiratory group b. dorsal respiratory group c. central pattern generator d. ventral respiratory group e. medullary respiratory group
a. pontine respiratory group.
Obligatory reabsorption sodium but not water occurs in the: a. proximal convoluted tubule b. distal convoluted tubule c. ascending loop of Henle d. both a and b
a. proximal convoluted tubule.
A given arteriole has a resistance of 2. What would the new resistance of this vessel be if its radius were to double? a. 1 b. 1/16 c. 1/8 d. 4
b. 1/16
. In an experiment, a drug is administered that increases the secretion of hydrogen ion by the Na+/H+ exchanger in the proximal renal tubules. It is observed that the pH of the urine is now 6.8. With which of the following is this hydrogen ion most likely to complex? a. Albumin b. Ammonia c. Bicarbonate d. Chloride e. Phosphate
b. Ammonia
Which of the following choices correctly traces the route of glomerular filtrate on its path to the collecting duct of a nephron? a. proximal tubule, Bowman's capsule, descending loop of Henle, ascending loop of Henle, distal tubule b. Bowman's capsule, proximal tubule, descending loop of Henle, ascending loop of Henle, distal tubule c. Bowman's capsule, distal tubule, descending loop of Henle, ascending loop of Henle, proximal tubule d. Bowman's capsule, proximal tubule, ascending loop of Henle, descending loop of Henle, distal tubule
b. Bowman's capsule, proximal tubule, descending loop of Henle, ascending loop of Henle, distal tubule.
Which of the following molecules binds to troponin during muscle contraction, triggering tropomyosin to move away from the actin binding sites and allowing the myosin head to form a cross bridge? a. ADP b. Calcium c. ATP d. Sodium
b. Calcium
A 79-year-old man is found down in his home by a neighbor. He is unarousable but has a pulse and respirations. Lung fields are clear on auscultation. His skin is bright pink with good turgor. Arterial blood gas analysis shows pH 7.48, PaO2 110 mm Hg, PaCO2 30 mm Hg, HCO3- 26 meQ/L, and oxygen saturation 60%. He is given oxygen by mask, with effective FiO2 of 50%, and repeat blood gas analysis shows pH 7.45, PaO2 320 mm Hg, PaCO2 30 mm Hg, HCO3- 25 meQ/L, and oxygen saturation 60%. Which of the following is the most likely diagnosis? a. Bronchial asthma b. Carbon monoxide poisoning c. Inhaled foreign body d. Pulmonary thromboembolism
b. Carbon monoxide poisoning.
Which of the following would be a symptom associated with diabetes mellitus? a. More concentrated urine b. Increased urine volume c. Less-frequent urination d. Decreased urine volume.
b. Increased urine volume
After the receptor is activated, _________ ion depolarizes the muscle fiber cell and travels through the ___________ a. Ca2+, Sarcoplasmic Reticulum b. Na+, T Tubules c. K+, Sarcomere d. Ca2+, Sarcomere e. Na+, Sarcoplasmic Reticulum
b. Na+, T Tubules
. Which heart valves are NOT actively closed by the contraction of muscular structures? a. Mitral valves b. Semilunar valves c. Atrioventricular valves d. Tricuspid valves
b. Semilunar valves
Which of the following is NOT innervated by the autonomic nervous system? a. Branching muscle cell b. Striated skeletal muscle cell c. Myocardial cell d. Intestinal muscle cell
b. Striated skeletal muscle cell
Which of the following correctly describes an isometric muscle contraction? a. There is a rapid burst of mechanical energy for a short powerful movement b. The amount of muscle tension increases without any change in the length of the muscle or the angle of the joint c. This form of contraction can either be eccentric or concentric d. The length of the muscle shortens and the angle of the joint changes during the contraction
b. The amount of muscle tension increases without any change in the length of the muscle or the angle of the joint
13. As glomerular filtrate moves through the ascending loop of Henle, the filtrate becomes more dilute: why? a. The ascending loop of Henle is permeable to water and ions. b. The ascending loop of Henle is permeable to ions but impermeable to water. c. The ascending loop of Henle is impermeable to water and ions. d. The ascending loop of Henle is permeable to water but not to ions.
b. The ascending loop of Henle is permeable to ions but impermeable to water. This allows for the reabsorption of ions, which makes the filtrate more dilute as it moves through the loop.
If free hemoglobin is found in an urine sample, indicating that red blood cells have been lysed, Which part of the nephron most likely caused the lysis of red blood cells? a. Collecting Duct b. The glomerulus c. Loop of Henle d. Proximal convoluted tubule
b. The glomerulus
Which of the following sections of the nephron does not change the osmolarity of the filtrate? a. The collecting duct. b. The proximal tubule c. Ascending loop of Henle d. Descending loop of Henle e. The distal tubule
b. The proximal tubule
The liver plays an important role in: a. blood clotting b. digestion of fats c. regulation of plasma glucose d. all of the above
b. digestion of fats, and c. regulation of plasma glucose.
35. Hyperventilation can result in: a. respiratory acidosis b. respiratory alkalosis c. respiratory compensation d. both a and c
b. respiratory alkalosis.
What is the role of acetylcholine in calcium release? a. Stimulates cellular contraction by opening voltage-gated ion channels b. Stimulates postsynaptic acetylcholine receptors to release intracellular calcium c. Binds to sarcoplasmic reticulum, causing calcium release d. Binds to the T-tubules, causing calcium release
c. Binds to the sarcoplasmic reticulum, causing calcium release.
The renal system does not play a direct role in regulating which of the following? a. Blood pH b. Blood solute concentrations c. Blood temperature d. Blood pressure
c. Blood temperature
Flow of blood within a muscular artery is measured. The flow is determined to be laminar. The flow through this artery is more likely to become turbulent with which of the following alterations? a. Blood flow velocity decreases b. Blood viscosity increases c. Focal narrowing occurs d. Hematocrit increases
c. Focal narrowing occurs.
Which of the following is not a function of the kidney? a. Control blood pH b. Excrete nitrogenous waste. c. Gluconeogenesis d. Maintain water balance.
c. Gluconeogenesis
44. In the sliding filament theory of muscle contraction, all but which of the following are functions of ATP? a. It moves the myosin head into a high energy "cocked" position b. It allows the myosin head to detach from the actin filament c. It moves tropomyosin off of actin binding sites d. ATP does all of these things during muscle contraction
c. It moves tropomyosin off of actin binding sites
Bicarbonate is an important buffer in blood and its concentration is regulated by the: a. Liver b. Pancreas c. Kidneys d. Lungs e. Red blood cells
c. Kidneys.
2. Which of the following is most directly responsible for concentrating urine in the kidney? a. Glomerus b. Bowman's capsule c. Loop of Henle d. Proximal convoluted tubule
c. Loop of Henle
All of the following features are unique to cardiac muscle cells except: a. They form branching chains b. There are gap junctions between cells c. They are non-striated d. They are linked together via intercalated discs
c. They are non-striated
What is the role of tropomyosin in muscle contraction? a. To release troponin from tropomyosin, allowing myosin to bind to the actin filament b. To release calcium from the sarcoplasmic reticulum c. To prevent myosin from continuing to slide up the actin filament d. To aid in myosin 'cocking' on the actin filament
c. To prevent myosin from continuing to slide up the actin filament.
A decrease in the affinity of hemoglobin for oxygen caused by the binding of a hydrogen ion to hemoglobin is described by the: a. carbamino effect. b. Henderson-Hasselbalch effect. c. Haldane effect d. Bohr effect
d. Bohr effect.
14. Which of the following has a rate of urinary excretion (units of solute per unit time) that is almost always identical to its rate of glomerular filtration in a healthy adult? a. Sodium b. Glucose c. Chloride d. Creatinine
d. Creatinine.
11. Urine is formed in a three-step process: which of the following gives the correct order in which these steps take place in the nephron? a. Glomerular filtration, tubular secretion, tubular reabsorption b. Tubular secretion, tubular reabsorption, glomerular filtration c. Tubular reabsorption, tubular secretion, glomerular filtration d. Glomerular filtration, tubular reabsorption, tubular secretion
d. Glomerular filtration, tubular reabsorption, tubular secretion
A 75-year-old man is brought to the emergency department in a comatose condition. He is afebrile. There are no external signs of trauma. A urine drug screen is positive for opiates. An arterial blood gas measurement shows: pH 7.35, PaO2 60 mm Hg, PaCO2 46 mm Hg, and HCO3- 27 meq/L. Which of the following is most likely to account for these findings? a. Acute blood loss b. Altitude sickness c. Carbon monoxide poisoning d. Hypoventilation e. Ketoacidosis
d. Hypoventilation.
A 19-year-old man incurs a laceration to his forearm and quickly loses a liter of blood. His blood pressure on arrival of paramedics is 80/40 mm Hg. Which of the following hormonal changes is most likely to occur from his blood loss? a. Decreased aldosterone b. Decreased renin c. Decreased vasopressin d. Increased angiotensin II e. Increased b-type natriuretic factor f. Increased glucagon
d. Increased angiotensin II
12. Which of the following is least likely to be present in the glomerular filtrate (the filtrate produced by the nephron before it enters the loop of Henle) of a healthy adult nephron? a. Amino acids b. Glucose c. Electrolytes d. Large molecular weight protein
d. Large molecular weight protein
39. We would expect to find smooth muscle in all of the following EXCEPT: a. Pulmonary circulatory tissue b. Esophagus c. Small intestine d. Myocardial tissue
d. Myocardial tissue
Which of the following anatomical portions of a nephron connects the Bowman's capsule to the loop of Henle? a. Distal convoluted tubule b. Collecting duct c. Connecting tubule d. Proximal convoluted tubule
d. Proximal convoluted tubule
How many nephrons does the average adult human kidney contain (a nephron is the main functional unit of the kidney)? a. Roughly 1000 b. 1 c. Roughly 100,000 d. Roughly 1,000,000
d. Roughly 1,000,000
The space between two Z lines constitutes the: a. Sarcolemma b. Sarcophagus c. Sarcoplasm d. Sarcomere
d. Sarcomere
1. Which of the following processes occurs in the kidney? a. Filtration b. Secretion c. Reabsorption d. The kidney uses all of the listed processes.
d. The kidney uses all of the listed processes.
Which of the following is accurate regarding Type I and Type II muscle fibers? a. Type I fibers store much of their energy as triglycerides, whereas Type II fibers store energy as ATP or creatine phosphate b. Type I fibers are easily fatigued and are therefore intended for short bursts of activity c. Type I fibers employ anaerobic metabolism, whereas Type II fibers utilize aerobic metabolism d. Type I fibers are white, whereas Type II fibers are red.
d. Type I fibers are white, whereas Type II fibers are red
How can the circulatory system promote heat retention/conservation, such as on a cold day? a. Decreasing tunica media contraction b. Increasing capillary surface area c. Vasodilation d. Vasoconstriction
d. Vasoconstriction
During an operative procedure on an adult patient, general anesthesia includes intubation and mechanical ventilation with a mixture of 70% nitrous oxide (N2O) and 30% oxygen (O2). During the procedure the patient becomes bradycardic and the level of anesthesia drops. Pharmacologic therapy is administered to increase the heart rate, and the desired level of anesthesia returns. Oxygen saturation remains stable during this time. Which of the following pulmonary physiologic parameters is most likely to explain these findings? a. Perfusion-limited gas exchange b. Diffusion-limited gas exchange c. Anemia d. Ventilation without perfusion
d. Ventilation without perfusion
Fluid leaving the distal convoluted tubule enters the a. proximal convoluted tubule b. ascending loop of Henle c. descending loop of Henle d. collecting duct
d. collecting duct.
Most of the carbon dioxide transported by the blood is: a. dissolved in plasma b. bound to hemoglobin c. nonspecifically bound to plasma proteins d. in the form of bicarbonate
d. in the form of bicarbonate
__________ heads stay bound to actin until _____________. a. troponin, more Ca2+ enters the cell b. myosin, more Ca2+ enters the cell c. tropomyosin, mare Ach is released d. myosin, another ATP binds e. troponin, another depolarization event occurs
d. myosin, another ATP binds
The primary effect of increased PO2 in the lungs is to cause ________ which ________ the ventilation-perfusion ratio back to a normal level. a. bronchodilation: increases. b. vasodilation: decreases. c. bronchoconstriction: decreases. d. vasoconstriction: increases. e. vasoconstriction: decreases.
d. vasoconstriction: increases the ventilation-perfusion ratio back to a normal level.
The neurotransmitter that excites the muscle fiber is _____________. a. GABA b. Na+ c. Ca2+ d. Troponin e. Acetylcholine
e. Acetylcholine
What is the primary determinant of airway resistance? a. Presence of mucus b. Compliance c. Traction competency d. Rate of air exchange e. Airway radius
e. Airway radius.
Which statement best describes the effect on the body due to pH changes either above or below the normal range? a. pH ranges vary throughout the body; therefore, blood pH has no detrimental effects on the body as it changes pH. b. Changes in pH destroy the nephrons of the kidney, making kidney failure inevitable. c. Changes in pH out of the normal range are normal and will not have any detrimental effects on the body. d. Changes in pH can only lower pH causing acidosis, meaning organs deteriorate due to high levels of acid. e. Changes in pH can denature proteins that serve as enzymes and receptors throughout the body, resulting in widespread effects on the body.
e. Changes in pH can denature proteins that serve as enzymes and receptors throughout the body, resulting in widespread effects on the body.
Peripheral chemoreceptors are specialized cells in contact with arterial blood that respond directly to changes in blood: a. pH b. pO2 c. PCO2 d. pCO2 and pO2 e. PCO2, pO2 and pH
e. PCO2, pO2, and pH.
A 58-year-old woman with a 70 pack year history of smoking has had increasing dyspnea for the past 6 years. On physical examination she has expiratory wheezes. A chest radiograph shows flattening of the diaphragmatic leaves bilaterally. Which of the following is the most significant stimulus to increase her respiratory rate? a. Blood pressure 80/40 mm Hg b. Heart rate 60/min c. Hematocrit 35% d. PaCO2 40 mm Hg e. PaO2 50 mm Hg
e. PaO2 50 mm Hg.
A 53-year-old woman has a 70 pack year history of smoking. She has dyspnea, particularly with exertion. On physical examination there are expiratory wheezes, but her lung fields are clear and tympanitic on percussion. An arterial blood gas shows pH 7.35, PaO2 70 mm Hg, PaCO2 50 mm Hg, and HCO3- 30 meq/L. Which of the following adaptations is most likely to occur if her PaO2 remains at 70 mm Hg? a. Systemic hypertension b. Increased preload c. Pulmonary arterial hypotension d. Sodium diuresis e. Tachypnea
e. Tachypnea.