Chapter 42

25 July 2022
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question
To adjust blood pressure independently in the capillaries of the gas-exchange surface and in the capillaries of the general body circulation, an organism would need a(n) _____. A) open circulatory system B) hemocoel C) two-chambered heart D) four-chambered heart
answer
D) four - chambered heart
question
In an open circulatory system, blood is _____. A) always inside of vessels and is under higher pressure than in closed circulatory systems B) not always confined to blood vessels and is under higher pressure than in closed circulatory systems C) always inside of vessels and is under lower pressure than in closed circulatory systems D) not always confined to blood vessels and is under lower pressure than in closed circulatory systems
answer
D) not always confined to blood vessels and is under lower pressure than in closed circulatory systems
question
Circulatory systems compensate for _____. A) temperature differences between the lungs and the active tissue B) the slow rate at which diffusion occurs over large distances C) the problem of communication systems involving only the nervous system D) the need to cushion animals from trauma
answer
B) the slow rate at which diffusion occurs over large distances
question
Which of the following develops the greatest pressure on the blood in the mammalian aorta? A) systole of the left atrium B) diastole of the right ventricle C) systole of the left ventricle D) diastole of the right atrium
answer
C) systole of the left ventricle
question
Which of the following is the correct sequence of blood flow in birds and mammals? A) left ventricle → aorta → lungs → systemic circulation B) vena cava → right atrium → right ventricle → pulmonary vein C) pulmonary vein → left atrium → left ventricle → pulmonary circuit D) vena cava → right atrium → right ventricle → pulmonary artery
answer
D) vena cava → right atrium → right ventricle → pulmonary artery
question
A patient with a blood pressure of 120/75, a pulse rate of 70 beats/minute, a stroke volume of 70 mL/beat (milliliters per beat), and a respiratory rate of 25 breaths/minute will have a cardiac output of _____. A) 1,000 mL/minute B) 1,750 mL/minute C) 2,800 mL/minute D) 4,900 mL/minute
answer
D) 4,900 mL/ minute
question
Damage to the sinoatrial node in humans _____. A) would block conductance between the bundle branches and the Purkinje fibers B) would have a negative effect on peripheral resistance C) would disrupt the rate and timing of cardiac muscle contractions D) would have a direct effect on blood pressure monitors in the aorta
answer
C) would disrupt the rate and timing of cardiac muscle contractions
question
A stroke volume of 70 mL/cycle in a heart with a pulse of 72 cycles per minute results in a cardiac output of about _____. A) 5 liters per minute B) 50 milliliters per minute C) 0.5 liters per minute D) 50 liters per minute
answer
A) 5 liters per minute
question
Atria contract _____. A) just prior to the beginning of diastole B) during diastole C) immediately after systole D) during systole
answer
D) during systole
question
The greatest difference in the concentration of respiratory gases is found in which of the following pairs of mammalian blood vessels? A) the pulmonary vein and the jugular vein B) the veins from the right and left legs C) the pulmonary artery and the inferior vena cava D) the pulmonary vein and the aorta
answer
A) the pulmonary vein and the jugular vein
question
A human red blood cell in an artery of the left arm is on its way to deliver oxygen to a cell in the thumb. To travel from the artery to the thumb and then back to the left ventricle, this red blood cell must pass through _____. A) one capillary bed B) two capillary beds C) three capillary beds D) four capillary beds
answer
B) two capillary beds
question
If a molecule of carbon dioxide released into the blood in your left toe is exhaled from your nose, it must pass through all of the following EXCEPT _____. A) the pulmonary vein B) an alveolus C) the trachea D) the right atrium
answer
A) the pulmonary vein
question
Among the following choices, which organism likely has the highest systolic pressure? A) mouse B) human C) hippopotamus D) giraffe
answer
D) giraffe
question
The velocity of blood flow is the lowest in capillaries because _____. A) the capillaries have internal valves that slow the flow of blood B) the diastolic blood pressure is too low to deliver blood to the capillaries at a high flow rate C) the systemic capillaries are supplied by the left ventricle, which has a lower cardiac output than the right ventricle D) the total cross-sectional area of the capillaries is greater than the total cross-sectional area of the arteries or any other part of the circulatory system
answer
D) the total cross-sectional area of the capillaries is greater than the total cross - sectional area of the arteries or any other part of the circulatory system
question
A species that has a normal resting systolic blood pressure of greater than 260 mm Hg is likely to be _____. A) an animal that is small and compact, without the need to pump blood very far from the heart B) a species that has very wide diameter veins C) an animal that has a very long distance between its heart and its brain D) an animal that makes frequent, quick motions
answer
C) an animal that has a very long distance between its heart and its brain
question
Small swollen areas in the neck, groin, and axillary region are associated with _____. A) increased activity of the immune system B) blood sugar that is abnormally high C) dehydration D) sodium depletion
answer
A) increased activity of the immune system
question
What will be the long-term effect of blocking the lymphatic vessels associated with a capillary bed? A) more fluid entering the venous capillaries B) an increase in the blood pressure in the capillary bed C) the accumulation of more fluid in the interstitial areas D) the area of the blockage becoming abnormally small
answer
C) the accumulation of more fluid in the interstitial areas
question
Which of the following conditions would most likely be due to high blood pressure in a mammal? A) bursting of blood vessels in capillary beds B) inability of the right ventricle to contract C) reversal of normal blood flow direction in arteries D) destruction of red blood cells
answer
A) bursting of blood vessels in the capillary beds
question
Which of the following mechanisms are used to regulate blood pressure in the closed circulatory system of vertebrates? I) changing the force of heart contraction II) constricting and relaxing sphincters in the walls of arterioles III) adjusting the volume of blood contained in the veins A) only I and II B) only I and III C) only II and III D) I, II, and III
answer
D) I, II, and III
question
Blood is pumped at high pressures in arteries from the heart to ensure that all parts of the body receive adequate blood flow. Capillary beds, however, would hemorrhage under direct arterial pressures. How does the design of the circulatory network contribute to reducing blood pressure to avoid this scenario? A) Blood flow through the capillaries is essentially frictionless, and this reduces the amount of pressure on their walls. B) The total cross-sectional diameter of the arterial circulation increases with progression from artery to arteriole to capillary, leading to a reduced blood pressure. C) Fluid loss from the arteries is high enough that pressure drops off significantly by the time blood reaches the capillaries. D) Capillary beds have the thickest walls of any blood vessel to resist these high pressures.
answer
B) The total cross-sectional diameter of the arterial circulation increases with progression from artery to arteriole to capillary, leading to a reduced blood pressure.
question
If, during protein starvation, the osmotic pressure on the venous side of capillary beds drops below the hydrostatic pressure, then _____. A) hemoglobin will not release oxygen B) fluids will tend to accumulate in tissues C) the pH of the interstitial fluids will increase D) plasma proteins will escape through the endothelium of the capillaries
answer
B) fluids will tend to accumulate in tissues
question
Large proteins such as albumin remain in capillaries rather than diffusing out, resulting in the _____. A) loss of osmotic pressure in the capillaries B) development of an osmotic pressure difference across capillary walls C) loss of fluid from capillaries D) increased diffusion of hemoglobin
answer
B) development of an osmotic pressure difference across capillary walls
question
The production of red blood cells is stimulated by _____. A) low-density lipoproteins B) immunoglobulins C) erythropoietin D) epinephrine
answer
C) erythropoietin
question
To become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross _____. A) one membrane—that of the lining in the lungs—and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood B) two membranes—in and out of the cell lining the lung—and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood C) four membranes—in and out of the cell lining the lung, in and out of the endothelial cell lining an alveolar capillary—and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood D) five membranes—in and out of the cell lining the lung, in and out of the endothelial cell lining an alveolar capillary, and into the red blood cell—to bind with hemoglobin
answer
D) five membranes—in and out of the cell lining the lung, in and out of the endothelial cell lining an alveolar capillary, and into the red blood cell—to bind with hemoglobin
question
The diagnosis of hypertension in adults is based on the _____. A) measurement of fatty deposits on the endothelium of arteries B) measurement of the LDL/HDL ratio in peripheral blood C) percentage of blood volume made up of platelets D) blood pressure being greater than 140 mm Hg systolic and/or greater than 90 mm Hg diastolic
answer
D) blood pressure being greater than 140 mm Hg systolic and/or greater than 90 mm Hg diastolic
question
Cyanide poisons mitochondria by blocking the final step in the electron transport chain. Human red blood cells placed in an isotonic solution containing cyanide are likely to _____. A) retain the normal cell shape, but the mitochondria will be poisoned B) lyse as the cyanide concentration increases inside the cell C) switch to anaerobic metabolism D) be unaffected
answer
D) be unaffected
question
A normal event in the process of blood clotting is the _____. A) production of erythropoietin B) conversion of fibrin to fibrinogen C) activation of prothrombin to thrombin D) synthesis of hemoglobin
answer
C) activation of prothrombin to thrombin
question
You cut your finger, and after putting pressure on the wound for several minutes, you notice that it is still bleeding profusely. What may be the problem? A) Platelets are not functioning properly, or there are too few to be effective. B) Mast cells are not releasing their chemical messengers. C) There are too many antigens to allow clotting. D) Hemoglobin levels are too high to allow clotting.
answer
A) Platelets are not functioning properly, or there are too few to be effective.
question
The hormone that stimulates the production of red blood cells, and the organ where this hormone is synthesized, are _____. A) growth hormone and pancreas, respectively B) erythropoietin and kidney, respectively C) cortisol and adrenal gland, respectively D) acetylcholine and bone marrow, respectively
answer
B) erythropoietin and kidney, respectively
question
When the air in a testing chamber is specially mixed so that its oxygen content is 10 percent and its overall air pressure is 400 mm Hg, then is _____. A) 400 mm Hg B) 82 mm Hg C) 40 mm Hg D) 4 mm Hg
answer
C) 40 mm Hg
question
The sun shining on a tidal pool during a hot day heats the water. As some water evaporates, the pool becomes saltier, causing _____. A) an increase in its carbon dioxide content B) a decrease in its oxygen content C) an increase in its ability to sustain aerobic organisms D) a decrease in the water's density
answer
B) a decrease in its oxygen content
question
Atmospheric pressure at sea level is equal to a column of 760 mm Hg. Oxygen makes up 21 percent of the atmosphere by volume. The partial pressure of oxygen ( ) in such conditions is _____. A) 160 mm Hg B) 16 mm Hg C) 21/760 D) 760/21
answer
A) 160 mm Hg
question
Some human infants, especially those born prematurely, suffer serious respiratory failure because of _____. A) the sudden change from the uterine environment to the air B) the overproduction of surfactants C) lung collapse due to inadequate production of surfactant D) mutations in the genes involved in lung formation
answer
C) lung collapse due to inadequate production of surfactant
question
At the summit of a high mountain, the atmospheric pressure is 380 mm Hg. If the atmosphere is still composed of 21percent oxygen, then the partial pressure of oxygen at this altitude is about _____. A) 80 mm Hg B) 160 mm Hg C) 380 mm Hg D) 760 mm Hg
answer
A) 80 mm Hg
question
Compared with the interstitial fluid that bathes active muscle cells, blood reaching these muscle cells in arteries has a _____. A) higher PO2 B) greater bicarbonate concentration C) lower pH D) lower osmotic pressure
answer
A) higher PO2
question
A rabbit taken from a meadow near sea level and moved to a meadow high on a mountainside would have some trouble breathing. Why? A) The percentage of oxygen in the air at high elevations is lower than at sea level. B) The percentage of oxygen in the air at high elevations is higher than at sea level. C) The partial pressure of oxygen in the air at high elevations is lower than at sea level. D) The partial pressure of oxygen in the air at high elevations is higher than at sea level.
answer
C) The partial pressure of oxygen in the air at high elevations is lower than at sea level.
question
Under identical atmospheric conditions, freshwater _____. A) has more oxygen than seawater B) has less oxygen than seawater C) can hold 10-40 times more carbon dioxide than air D) can hold 10-40 times more oxygen than air
answer
A) has more oxygen than seawater
question
Which of the following statements comparing respiration in fish and in mammals is correct? A) The respiratory medium for fish carries more oxygen than the respiratory medium of mammals. B) A countercurrent exchange mechanism between the respiratory medium and blood flow is seen in mammals but not in fish. C) The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional. D) In blood, oxygen is primarily transported by plasma in fish, but by red blood cells in mammals.
answer
C) The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.
question
Carbon dioxide levels in the blood and cerebrospinal fluid affect pH. This enables the organism to sense a disturbance in gas levels as _____. A) the brain directly measures and monitors oxygen levels and causes breathing changes accordingly B) the medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing C) the brain alters the pH of the cerebrospinal fluid to force the animal to retain more or less carbon dioxide D) stretch receptors in the lungs cause the medulla oblongata to speed up or slow breathing
answer
B) the medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing
question
A person with a tidal volume of 450 mL (milliliters), a vital capacity of 4000 mL, and a residual volume of 1000 mL would have a potential total lung capacity of _____. A) 1450 mL B) 4000 mL C) 4450 mL D) 5000 mL
answer
D) 5000 mL
question
During most daily activities, the human respiration rate is most closely linked to the blood levels of _____. A) nitrogen B) oxygen C) carbon dioxide D) carbon monoxide
answer
C) carbon dioxide
question
An decrease from pH 7.4 to pH 7.2 causes hemoglobin to _____. A) release all bound carbon dioxide molecules B) bind more oxygen molecules C) increase its binding of H+ D) give up more of its oxygen molecules
answer
C) increase its binding of H+
question
The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in _____. A) the partial pressure of oxygen B) hemoglobin concentration C) temperature D) pH
answer
D) pH
question
Most of the carbon dioxide produced by humans is _____. A) converted to bicarbonate ions by an enzyme in red blood cells B) bound to hemoglobin C) transported in the erythrocytes as carbonic acid D) simply dissolved in the plasma
answer
A) converted to bicarbonate ions by an enzyme in red blood cells
question
Which of the following events would be predicted by the Bohr shift effect as the amount of carbon dioxide released from your tissues into the blood capillaries increases? The amount of oxygen in _____. A) arterial blood would increase B) arterial blood would decrease C) venous blood would increase D) venous blood would decrease
answer
D) venous blood would decrease
question
You are a physician, and you are seeing a patient who complains of abnormal fatigue during exercise. You find that the immediate problem is a buildup of carbon dioxide in the tissues. What is the most likely cause? A) abnormally shaped platelets B) abnormal carbonic anhydrase C) abnormal hemoglobin D) not enough hemoglobin
answer
B) abnormal carbonic anhydrase
question
Carbonic anhydrase inhibitors cause less movement of carbonic acid toward carbon dioxide production and are used as a prophylactic treatment of altitude sickness. Altitude sickness occurs when a hiker ascends to altitudes where the density of oxygen is low. How does this decrease the symptoms of high altitude sickness? A) The excess hydrogen ions are excreted in the urine and the resulting loss of acidity increases respiration rate. B) The excess bicarbonate ions are excreted in the urine and the resulting loss of blood pressure increases respiration rate. C) The excess bicarbonate ions are excreted in the urine and the resulting increase in blood acidity leads to an increase in ventilation. D) The excess bicarbonate ions in the blood increase the affinity of hemoglobin for oxygen.
answer
C) The excess bicarbonate ions are excreted in the urine and the resulting increase in blood acidity leads to an increase in ventilation.