Chapter 42

25 July 2022
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question
What is the correct order of processes involving the movement of oxygen from the environment to mitochondria in vertebrates? A) ventilation, circulation, cellular respiration B) circulation, ventilation, cellular respiration C) diffusion in tissues, cellular respiration, diffusion at respiratory surface D) ventilation, diffusion in tissues, circulation E) circulation, cellular respiration, diffusion in tissues
answer
(A) ventilation, circulation, cellular respiration
question
Which of the following best describes the process of ventilation? A) the movement of oxygen gas through the blood of the circulatory system B) the movement of carbon dioxide gas through the blood of the circulatory system C) the movement of the respiratory medium past the respiratory surface D) the diffusion of gases into and out of the circulatory system E) the diffusion of gases into and out of tissues where cellular respiration occurs
answer
(C) the movement of the respiratory medium past the respiratory surface
question
In which location would you expect the oxygen concentration to be the lowest? A) the environment B) the blood C) the lungs D) within tissues E) the heart
answer
(D) within tissues
question
Which of the following respiratory systems is NOT closely associated with the blood supply? A) the lungs of a vertebrate B) the gills of a fish C) the tracheal system of an insect D) the skin of an earthworm
answer
(C) the tracheal system of an insect
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
Gas exchange is more difficult for aquatic animals with gills than for terrestrial animals with lungs because ________. A) water is less dense than air B) water contains much less oxygen per unit volume than air C) gills have less surface area than lungs D) gills allow only unidirectional transport E) gills collapse in air
answer
(B) water contains much less oxygen per unit volume than air
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 (PO2) in such conditions is ________. A) 160 mm Hg B) 16 mm Hg C) 120/75 D) 21/760 E) 760/21
answer
(A) 160 mm Hg
question
At an atmospheric pressure of 870 mm Hg with 21 percent oxygen, the partial pressure of oxygen is ________. A) 100 mm Hg B) 127 mm Hg C) 151 mm Hg D) 182 mm Hg E) 219 mm Hg
answer
(D) 182 mm Hg
question
At the summit of a high mountain, the atmospheric pressure is 380 mm Hg. If the atmosphere is still composed of 21 percent oxygen, then the partial pressure of oxygen at this altitude is about ________. A) 0 mm Hg B) 80 mm Hg C) 160 mm Hg D) 380 mm Hg E) 760 mm Hg
answer
(B) 80 mm Hg
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 PO2 is ________. A) 400 mm Hg B) 82 mm Hg C) 40 mm Hg D) 21 mm Hg E) 4 mm Hg
answer
(C) 40 mm Hg
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
The air pressure in Denver, Colorado, is about 83 percent of the air pressure in Miami Beach, which is at about sea level. Given that the air pressure in Miami Beach is 760 mm Hg and oxygen makes up 21 percent of the air in Miami Beach, what are the percentage of oxygen and the partial pressure of oxygen in Denver? A) 21 percent; 21 mm Hg B) 21 percent; 132 mm Hg C) 17.4 percent; 132 mm Hg D) 17.4 percent; 21 mm Hg
answer
(B) 21 percent; 132 mm Hg
question
Breathing is primarily regulated by ________. A) erythropoietin levels in the blood B) the concentration of red blood cells C) hemoglobin levels in the blood D) carbon dioxide concentration and pH sensors E) the lungs and the larynx
answer
(D) carbon dioxide concentration and pH sensors
question
Carbon dioxide levels in the blood and in cerebrospinal fluid affect pH of these fluids. 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) neurons in contact with cerebrospinal fluid monitor pH and use 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 E) the medulla oblongata is able to control the concentration of bicarbonate ions in the blood
answer
(B) neurons in contact with cerebrospinal fluid monitor pH and use this measure to control breathing
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
Determine the rate of diffusion (cm3/min or mL/min) in the gas-exchange organ of an air- breathing animal where the area for gas exchange in the lung is 2 cm2, the diffusion constant is 0.08 cm2/min, the PO2 (partial pressure of oxygen) of the air in the lung is 140 mm Hg, the PO2 in blood flowing into the lung is 90 mm Hg, and the thickness of the gas exchange membrane is 0.0001 cm. A) 80,000 B) 125 C) 32,000 D) 10,00,000
answer
(A) 80,000
question
Under identical atmospheric conditions, freshwater ________. A) has more oxygen than seawater B) has less oxygen than seawater C) can hold 10β€”40 times more carbon dioxide than air D) can hold 10β€”40 times more oxygen than air
answer
(A) has more oxygen than seawater
question
If other factors are equal, which of the following environments would have the highest level of dissolved oxygen? A) warm, salty water at low elevation B) cool, salty water at low elevation C) warm freshwater at high elevation D) cool freshwater at high elevation E) cool freshwater at low elevation
answer
(E) cool freshwater at low elevation
question
Countercurrent exchange is evident in the flow of ________. A) water across the gills of a fish and the blood within those gills B) blood in the dorsal vessel of an insect and that of air within its tracheae C) air within the primary bronchi of a human and the blood within the pulmonary veins D) water across the skin of a frog and the blood flow within the ventricle of its heart
answer
(A) water across the gills of a fish and the blood within those gills
question
Countercurrent exchange in the fish gill helps to maximize ________. A) endocytosis B) blood pressure C) extraction of oxygen from the water D) active transport E) osmosis
answer
(C) extraction of oxygen from the water
question
Air-breathing insects carry out gas exchange ________. A) in their specialized external gills B) in their specialized internal gills C) in the alveoli of their lungs D) across the finest branches of the trachea and cell membranes E) across all parts of their thin cuticular exoskeleton
answer
(D) across the finest branches of the trachea and cell membranes
question
Air rushes into the lungs of humans during inhalation because ________. A) the rib muscles and diaphragm contract, increasing the lung volume and decreasing the pressure within the lungs B) the volume of the alveoli increases as smooth muscles contract C) gas flows from a region of lower pressure to a region of higher pressure D) pulmonary muscles contract and pull on the outer surface of the lungs E) a positive respiratory pressure is created when the diaphragm relaxes
answer
(A) the rib muscles and diaphragm contract, increasing the lung volume and decreasing the pressure within the lungs
question
The exhalation of air from human lungs is driven by ________. A) a decrease in the volume of the thoracic cavity with an associated increase in thoracic pressure B) a decrease in the residual volume of the lungs C) the contraction of the diaphragm D) the closure of the epiglottis E) the expansion of the rib cage
answer
(A) a decrease in the volume of the thoracic cavity with an associated increase in thoracic pressure
question
As a person goes from rest to full-effort exercise, there is an increase in the ________. A) tidal volume B) vital capacity C) residual volume D) total lung capacity
answer
(A) tidal volume
question
Some animals have no gills when young but then develop gills that grow larger as the animal grows larger. What is the reason for this increase in gill size? A) The young of these animals are much more active than the adult, which leads to a higher BMR (basal metabolic rate) and, therefore, a higher need for oxygen. B) Relative to their volume, the young have more surface area across which they can transport all the oxygen they need. C) The young have a higher basal metabolic rate. D) Relative to their surface area, the young have more body volume in which they can store oxygen for long periods of time.
answer
(B) Relative to their volume, the young have more surface area across which they can transport all the oxygen they need.
question
What adaptations are observed in trachea and lungs to reduce water loss? A) A countercurrent exchange system reduces water loss in animals with either trachea or lungs. B) The location of the trachea and lungs (inside of the body) reduces water loss. C) Trachea and lungs secrete specialized oxygen-carrying chemicals to reduce water loss. D) Limbs are used by animals with trachea or lungs to move water over these structures.
answer
(B) The location of the trachea and lungs (inside of the body) reduces water loss.
question
A significant increase in the amount of interstitial fluid surrounding the capillary beds of a human's lungs will cause ________. A) an increase in the amount of carbon dioxide moving from the blood to the lungs B) an increase in the amount of oxygen moving from the lungs into the blood C) a decrease in the amount of oxygen moving from the lungs into the blood D) an increase of pressure that would cause the capillary beds to burst E) a decrease in the amount of work needed for effective ventilation of the lungs
answer
(C) a decrease in the amount of oxygen moving from the lungs into the blood
question
Fick's law of diffusion describes the factors that influence the diffusion of respiratory gases across biological membranes like gills and lungs. Diffusion rate = k Γ— A Γ— (P2 βˆ’ P1)/D. Natural selection is LEAST likely to act upon which variable in Fick's law? A) A B) k C) P2 βˆ’ P1 D) D
answer
(B) k
question
If the inner lining of the air sacs is neither thin nor highly vascularized, then what can be inferred about the air sacs? A) They must not belong to the respiratory system. B) They cannot be derived from endoderm. C) They are not efficient sites of gas exchange between air and blood. D) They must obtain nutrition from some source other than the bloodstream. E) They cannot effectively moisturize the air before it reaches the lungs.
answer
(C) They are not efficient sites of gas exchange between air and blood.
question
Some bird bones are hollow rather than honeycombed. The hollow bones mostly contain air sacs. The replacement of bone marrow with air sacs is properly understood as an adaptation that ________. 1. reduces the weight of the bird 2. facilitates flight 3. eliminates the functions of bone marrow A) only 1 B) only 2 C) only 3 D) 1 and 2 E) 1, 2, and 3
answer
(D) 1 and 2
question
Birds generate a lot of heat, especially during flight. Yet the adipose tissue under their skin and the feathers atop their skin make it difficult to eliminate excess heat across the skin. Which of the following alternatives can absorb body heat and eliminate it from the bird most effectively? A) air in the air sacs B) lymph in the lymphatic vessels C) blood in the vessels D) blood in the heart E) urine in the bladder
answer
(A) air in the air sacs
question
The movement of air along parabronchi is most similar to the movement of ________. A) air in the lungs of other amniotes B) food/waste in a gastrovascular cavity C) a mouse passing through the digestive system of a snake D) the frog tongue during feeding E) air in lungs of terrestrial amphibians
answer
(C) a mouse passing through the digestive system of a snake
question
Which type of bird is most likely to benefit from air sacs that reduce its weight? A) birds, such as geese, which migrate great distances B) birds that chip away wood, such as woodpeckers C) diving birds D) birds that rip apart prey, such as hawks and eagles
answer
(A) birds, such as geese, which migrate great distances
question
The one-way flow of air along parabronchi makes what type of gas-exchange mechanism possible, at least theoretically? A) the same as that occurring in fish gills B) the same as that occurring in insect tracheae C) the same as that occurring in mammalian lungs D) the same as that occurring in echinoderm skin gills
answer
(A) the same as that occurring in fish gills
question
What would be the consequences if we were to reverse the direction of water flow over the gills of a fish, moving water inward past the operculum, past the gills, then out of the mouth? This reversal of water flow would ________. A) reduce the efficiency of gas exchange B) change the exchange of gases in the body from carbon dioxide out and oxygen in to carbon dioxide in and oxygen out C) increase the efficiency of gas exchange
answer
(A) reduce the efficiency of gas exchange
question
When you are jogging, your muscles are using more oxygen and releasing more carbon dioxide into the blood than when you are at home on the couch. Which of the following would occur during your jog? A) Blood pH would become more basic. B) The concentration of bicarbonate ions (HCO3βˆ’) in the blood would decrease. C) The medullary respiratory center would detect rising carbon dioxide levels. D) The volume of the dead air space would decrease.
answer
(C) The medullary respiratory center would detect rising carbon dioxide levels.
question
When you hold your breath, which of the following blood gas changes first leads to the urge to breathe? A) rising oxygen B) falling oxygen C) rising carbon dioxide D) falling carbon dioxide
answer
(C) rising carbon dioxide
question
In mammals, gas exchange between the atmosphere and the pulmonary blood occurs in the ________. A) trachea B) larynx C) bronchi D) bronchioles E) alveoli
answer
(E) alveoli
question
In what way does hemoglobin act as a buffer against changes in blood pH? A) Subsequent binding of oxygen is drastically reduced after the first one is bound. B) Hemoglobin binds some of the excess protons released by carbonic acid. C) Hemoglobin produces protons or hydroxide ions as needed to alter the blood pH. D) Hemoglobin removes excess protons from the red blood cells so that they can be excreted through the kidneys.
answer
(B) Hemoglobin binds some of the excess protons released by carbonic acid.
question
To become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross ________. A) zero membranes-oxygen binds directly to hemoglobin, a protein dissolved in the plasma of the blood B) one membrane-that of the lining in the lungs-and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood C) two membranes-in and out of the cells lining the lung-and then bind directly to hemoglobin, a protein dissolved in the plasma of the blood D) four membranes-in and out of the cells 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 E) 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
(E) 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
Which component of blood is responsible for the formation of blood clots? A) red blood cells B) white blood cells C) platelets D) all blood cells E) None of the above form blood clots.
answer
(C) platelets
question
An increase in blood carbon dioxide content causes hemoglobin to ________. A) release all bound carbon dioxide molecules B) bind more oxygen molecules C) denature D) increase its binding of H+ E) give up more of its oxygen molecules
answer
(D) 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) the partial pressure of carbon monoxide C) hemoglobin concentration D) temperature E) pH
answer
(E) pH
question
Most of the carbon dioxide produced by humans is ________. A) converted to bicarbonate ions by carbonic anhydrase, an enzyme in red blood cells B) bound to hemoglobin C) transported in the erythrocytes as carbonic acid D) simply dissolved in the plasma E) bicarbonate ions bound to hemoglobin
answer
(A) converted to bicarbonate ions by carbonic anhydrase, an enzyme in red blood cells
question
Compared with the interstitial fluid that bathes active muscle cells, blood reaching these muscle cells in arteries has a ________. A) higher PO2 B) higher PCO2 C) greater bicarbonate concentration D) lower pH E) lower osmotic pressure
answer
(A) higher PO2
question
Which of the following reactions prevails in red blood cells traveling through alveolar capillaries? (Hb = hemoglobin) A) Hb + 4 O2 β†’ Hb(O2)4 B) Hb(O2)4 β†’ Hb + 4 O2 C) CO2 + H2O β†’ H2CO3 D) H2CO3 β†’ H+ + HCO3βˆ’ E) Hb + 4 CO2 β†’ Hb(CO2)4
answer
(A) Hb + 4 O2 β†’ Hb(O2)4
question
In what way does hemoglobin act as a buffer against changes in blood pH? A) Subsequent binding of oxygen is drastically reduced after the first one is bound. B) Hemoglobin binds some of the excess protons released by carbonic acid. C) Hemoglobin produces protons or hydroxide ions as needed to alter the blood pH. D) Hemoglobin removes excess protons from the red blood cells so that they can be excreted through the kidneys.
answer
(B) Hemoglobin binds some of the excess protons released by carbonic acid.
question
Complete the statement correctly. Fetal hemoglobin ________. A) binds more carbon dioxide molecules than adult hemoglobin B) is better able to release oxygen than is adult hemoglobin C) has a higher affinity for oxygen than does adult hemoglobin D) is better able to release carbon dioxide than is adult hemoglobin E) has a higher affinity for carbon dioxide than does adult hemoglobin
answer
(C) has a higher affinity for oxygen than does adult hemoglobin
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
The oxygen content of water increases linearly with an increase in oxygen partial pressure, whereas the oxygen content of blood increases in a sigmoidal (S-shaped) fashion. Why? A) Carbonic anhydrase contributes to carbon dioxide release in blood, but not water. B) The Bohr shift is stronger in water than in blood. C) Hemoglobin shows cooperative oxygen binding. D) Oxygen is transported equally by hemoglobin and blood plasma.
answer
(C) Hemoglobin shows cooperative oxygen binding.
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
Altitude sickness occurs when a hiker ascends to altitudes where the density of oxygen is low. Carbonic anhydrase inhibitors cause less movement of carbonic acid toward carbon dioxide production and are used as a prophylactic treatment of altitude sickness. How does this treatment decrease the symptoms of high altitude sickness? A) The resulting rise in pH increases respiration rate. B) Excess bicarbonate ions are excreted in the urine and the resulting loss of blood pressure increases respiration rate. C) An increase in blood acidity leads to an increase in ventilation. D) An increase in bicarbonate ions in the blood stimulates the production of more red blood cells. E) The excess bicarbonate ions in the blood increase the affinity of hemoglobin for oxygen.
answer
(C) An increase in blood acidity leads to an increase in ventilation.
question
A large increase in albumin concentration in the plasma of a dog would result in which of the following? A) an increase in blood volume and a decrease in lymph volume B) a decrease in blood volume and an increase in lymph volume C) an increase in blood volume and an increase in lymph volume D) a decrease in blood volume and a decrease in lymph volume
answer
(A) an increase in blood volume and a decrease in lymph volume
question
The circulatory systems of bony fishes, rays, and sharks are most similar to ________. A) those of birds, with a four-chambered heart B) the portal systems of mammals, where two capillary beds occur sequentially, without passage of blood through a pumping chamber C) those of reptiles, with one pumping chamber driving blood flow to a gas-exchange organ, and a different pumping chamber driving blood to the rest of the circulation D) those of sponges, where gas exchange in all cells occurs directly with the external environment E) those of humans, where there are four pumping chambers to drive blood flow
answer
(B) the portal systems of mammals, where two capillary beds occur sequentially, without passage of blood through a pumping chamber
question
Organisms with a circulating body fluid that is distinct from the fluid that directly surrounds the body's cells are likely to have ________. A) an open circulatory system B) a closed circulatory system C) a gastrovascular cavity D) branched tracheae E) hemolymph
answer
(B) a closed circulatory system
question
In which of the following organisms does blood flow from the lungs to the heart before circulating through the rest of the body? A) annelids B) mollusks C) fishes D) frogs E) insects
answer
(D) frogs
question
The vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart are the ________. A) amphibians B) birds C) fishes D) mammals E) reptiles
answer
(C) fishes
question
To increase the output of the heart, what adjustments are made in the circulatory system? 1. an increase in heart rate 2. an increase in stroke volume of the heart 3. a reduced blood flow to the brain A) only 1 B) only 2 C) only 3 D) 1 and 2 E) 1, 2, and 3
answer
(D) 1 and 2
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 E) diastole of the left atrium
answer
(C) systole of the left ventricle
question
61) Which of the following is the correct sequence of blood flow in birds and mammals? A) left ventricle β†’ aorta β†’ lungs β†’ systemic circulation B) vena cava β†’ right atrium β†’ right ventricle β†’ pulmonary vein C) pulmonary vein β†’ left atrium β†’ left ventricle β†’ pulmonary circuit D) vena cava β†’ right atrium β†’ right ventricle β†’ pulmonary artery E) right atrium β†’ pulmonary artery β†’ left atrium β†’ ventricle
answer
(D) vena cava β†’ right atrium β†’ right ventricle β†’ 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) 70 mL/minute B) 1000 mL/minute C) 1750 mL/minute D) 2800 mL/minute E) 4900 mL/minute
answer
(E) 4900 mL/minute
question
Damage to the sinoatrial node in humans ________. A) is a major contributor to heart attacks B) would block conductance between the bundle branches and the Purkinje fibers C) would have a negative effect on peripheral resistance D) would disrupt the rate and timing of cardiac muscle contractions E) would have a direct effect on blood pressure monitors in the aorta
answer
(D) would disrupt the rate and timing of cardiac muscle contractions
question
A stroke volume of 70 mL/beat in a heart with a pulse of 72 beats 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 E) 500 liters per minute
answer
(A) 5 liters per minute
question
The aortic valve of the mammalian heart ________. A) is the route by which blood flows from the atria to the ventricles B) is found on the right side of the heart C) is the attachment site where the pulmonary veins empty into the heart D) prevents backflow of blood in the aorta E) is located where the anterior and posterior venae cavae empty into the heart
answer
(D) prevents backflow of blood in the aorta
question
What type of blood vessels has the slowest velocity of blood flow? A) arteries B) arterioles C) veins D) capillaries
answer
(D) capillaries
question
Among the following choices, which organism likely has the highest systolic pressure? A) mouse B) rabbit C) human D) hippopotamus E) giraffe
answer
(E) giraffe
question
The velocity of blood flow is the lowest in capillaries because ________. A) the capillary walls are not thin enough to allow oxygen to exchange with the cells B) the capillaries have internal valves that slow the flow of blood C) the diastolic blood pressure is too low to deliver blood to the capillaries at a high flow rate D) the systemic capillaries are supplied by the left ventricle, which has a lower cardiac output than the right ventricle E) 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
(E) 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
The blood pressure is lowest in the ________. A) aorta B) arteries C) arterioles D) left ventricle of the heart E) vena cava
answer
(E) vena cava
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) an animal with abundant lipid storage C) a species that has very wide diameter veins D) an animal that has a very long distance between its heart and its brain E) an animal that makes frequent, quick motions
answer
(D) an animal that has a very long distance between its heart and its brain
question
Heart rate will increase in the presence of increased ________. A) low-density lipoproteins B) immunoglobulins C) erythropoietin D) epinephrine E) platelets
answer
(D) epinephrine
question
An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, was well formed, and had four chambers, with no connection between the right and left sides. A reasonable conclusion supported by these observations is that the ________. A) animal had evolved from birds B) animal was endothermic and had a high metabolic rate C) animal was most closely related to alligators and crocodiles D) animal was likely an invertebrate animal E) species had little to no need to regulate blood pressure
answer
(B) animal was endothermic and had a high metabolic rate
question
Blood returning to the mammalian heart in a pulmonary vein drains first into the ________. A) vena cava B) left atrium C) right atrium D) left ventricle E) right ventricle
answer
(B) left atrium
question
Pulse is a direct measure of ________. A) blood pressure B) stroke volume C) cardiac output D) heart rate E) breathing rate
answer
(D) heart rate
question
One feature that amphibians and humans have in common is ________. A) the number of heart chambers B) the type of gas-exchange tissues C) a complete separation of circuits for circulation D) the number of circuits for circulation E) a low blood pressure in the systemic circuit
answer
(D) the number of circuits for circulation
question
Which of the four muscular chambers of the human heart directly propels blood into the pulmonary circulation? A) right atrium B) right ventricle C) left atrium D) left ventricle
answer
(B) right ventricle
question
An animal has a cardiac output of 40 mL/min (milliliters per minute) and a stroke volume of 5 mL. What is its heart rate? A) 8 beats/minute B) 200 beats/minute C) 12.5 beats/minute D) Heart rate cannot be determined with only these two variables.
answer
(A) 8 beats/minute
question
Atria contract ________. A) at the beginning of atrial diastole B) during atrial diastole C) immediately after ventricular systole D) during atrial systole
answer
(D) during atrial systole
question
The fluid that is moved by in the circulatory system of a typical arthropod is ________. A) digestive juices B) hemolymph C) blood plasma D) cytosol
answer
(B) hemolymph
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 E) the need that fetal organisms have for maintaining an optimal body temperature
answer
(B) the slow rate at which diffusion occurs over large distances
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 E) the inferior vena cava and the superior vena cava
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 E) five capillary beds
answer
(B) two capillary beds
question
What is present in arterioles that is NOT present in capillaries? A) white blood cells and platelets B) carbon dioxide C) a lining of endothelial cells D) circular smooth muscle cells
answer
(D) circular smooth muscle cells
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 the interstitial fluid and tissues. C) the pH of the interstitial fluid will increase D) most carbon dioxide will be bound to hemoglobin and carried away from tissues E) plasma proteins will escape through the endothelium of the capillaries
answer
(B) fluids will tend to accumulate in the interstitial fluid and 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 that favors fluid retention in the capillary C) loss of fluid from capillaries D) increased diffusion of carbon dioxide E) increased diffusion of hemoglobin
answer
(B) development of an osmotic pressure difference across capillary walls that favors fluid retention in the capillary
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 140/90 mm Hg (systolic/diastolic) E) number of leukocytes per cubic millimeter of blood
answer
(D) blood pressure being greater than 140/90 mm Hg (systolic/diastolic)
question
The plasma proteins and other solutes in the blood in humans ________. A) maintain the blood's osmotic pressure B) transport water-soluble lipids C) carry out gas exchange D) undergo aerobic metabolism E) transport oxygen
answer
(A) maintain the blood's osmotic pressure
question
If a molecule of carbon dioxide enters the blood in your left toe and 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 E) the right ventricle
answer
(A) the pulmonary vein
question
The atrioventricular (AV) node serves to ________. A) generate the heartbeat signal B) propagate the beat across the atria C) delay the heartbeat signal before transmitting it to the ventricles D) transmit the heartbeat signal to the apex of the ventricles E) cause the heart to relax
answer
(C) delay the heartbeat signal before transmitting it to the ventricles
question
The pacemaker cells are found in what structure? A) sinoatrial node B) the ventricles C) left atrium D) pulmonary veins E) aorta
answer
(A) sinoatrial node
question
Where is the velocity of blood the highest? A) inferior vena cava B) aorta C) small arteries D) superior vena cava E) capillaries
answer
(B) aorta
question
Blockage of vessels supplying blood to the heart itself is ________. A) called arteriosclerosis B) caused by hardening of the arteries C) called myocardial infarction or a heart attack D) prevented by the use of nicotine
answer
(C) called myocardial infarction or a heart attack
question
Myocardial infarction occurs when ________. A) arteries harden or lose their elasticity B) the electrical control of the heart leads to an elevated heart rate C) the heart stops D) blockage of blood vessels prevents adequate blood flow to the heart
answer
(D) blockage of blood vessels prevents adequate blood flow to the heart