Question 1

Gas exchange is more difficult for aquatic animals with gills than for terrestrial animals with lungs because

Accepted Answer

A)  water is less dense than air. 
B)  water contains much less O2 than air per unit volume. 
C)  gills have less surface area than lungs. 
D)  gills allow only unidirectional transport. 
E)  gills collapse in air. 
A)  water is less dense than air. 
B)  water contains much less O2 than air per unit volume. 
C)  gills have less surface area than lungs. 
D)  gills allow only unidirectional transport. 
E)  gills collapse in air.

Question 2

To become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross

Accepted Answer

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 cell 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 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. 
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. 
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 cell 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 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. 
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 3

An increase from pH 7.2 to pH 7.4 around hemoglobin causes

Accepted Answer

A)  hemoglobin to release all bound oxygen molecules. 
B)  an increase in the affinity of hemoglobin to bind oxygen molecules. 
C)  hemoglobin to denature. 
D)  an increase in the binding of H+ by hemoglobin. 
E)  hemoglobin to more readily give up its oxygen molecules. 
A)  hemoglobin to release all bound oxygen molecules. 
B)  an increase in the affinity of hemoglobin to bind oxygen molecules. 
C)  hemoglobin to denature. 
D)  an increase in the binding of H+ by hemoglobin. 
E)  hemoglobin to more readily give up its oxygen molecules.

Question 4

Which of the following respiratory systems is not closely associated with a blood supply?

Accepted Answer

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 
E)  the parapodia of a polychaete worm 
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 
E)  the parapodia of a polychaete worm

Question 5

Most of the carbon dioxide produced by humans is

Accepted Answer

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. 
E)  bicarbonate ions bound to hemoglobin. 
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. 
E)  bicarbonate ions bound to hemoglobin.

Question 6

Countercurrent exchange is evident in

Accepted Answer

A)  the flow of water across the gills of a fish and that of blood within those gills. 
B)  the flow of blood in the dorsal vessel of an insect and that of air within its tracheae. 
C)  the flow of air within the primary bronchi of a human and that of blood within the pulmonary veins. 
D)  the flow of water across the skin of a frog and that of blood within the ventricle of its heart. 
E)  the flow of fluid out of the arterial end of a capillary and that of fluid back into the venous end of the same capillary. 
A)  the flow of water across the gills of a fish and that of blood within those gills. 
B)  the flow of blood in the dorsal vessel of an insect and that of air within its tracheae. 
C)  the flow of air within the primary bronchi of a human and that of blood within the pulmonary veins. 
D)  the flow of water across the skin of a frog and that of blood within the ventricle of its heart. 
E)  the flow of fluid out of the arterial end of a capillary and that of fluid back into the venous end of the same capillary.

Question 7

Air-breathing insects carry out gas exchange

Accepted Answer

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. 
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.

Question 8

An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, 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

Accepted Answer

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. 
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.

Question 9

The production of red blood cells is stimulated by

Accepted Answer

A)  low-density lipoproteins. 
B)  immunoglobulins. 
C)  erythropoietin. 
D)  epinephrine. 
E)  platelets. 
A)  low-density lipoproteins. 
B)  immunoglobulins. 
C)  erythropoietin. 
D)  epinephrine. 
E)  platelets.

Question 10

The semilunar valves of the mammalian heart

Accepted Answer

A)  are the route by which blood flows from the atria to the ventricles. 
B)  are found only on the right side of the heart. 
C)  are the attachment site where the pulmonary veins empty into the heart. 
D)  prevent backflow of blood in the aorta and pulmonary arteries. 
E)  are at the places where the anterior and posterior venae cavae empty into the heart. 
A)  are the route by which blood flows from the atria to the ventricles. 
B)  are found only on the right side of the heart. 
C)  are the attachment site where the pulmonary veins empty into the heart. 
D)  prevent backflow of blood in the aorta and pulmonary arteries. 
E)  are at the places where the anterior and posterior venae cavae empty into the heart.

Question 11

The velocity of blood flow is the lowest in capillaries because

Accepted Answer

A)  the capillary walls are not thin enough to allow oxygen to exchange with the cells. 
B)  the capillaries are far from the heart, and blood flow slows as distance from the heart increases. 
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. 
A)  the capillary walls are not thin enough to allow oxygen to exchange with the cells. 
B)  the capillaries are far from the heart, and blood flow slows as distance from the heart increases. 
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.

Question 12

An increased concentration of nitric oxide within a vascular bed is associated with

Accepted Answer

A)  vasoconstriction. 
B)  vasodilation. 
C)  narrowing of the arteries. 
D)  a reduction in blood flow in that region. 
E)  a decreased amount of blood in the capillaries of that vascular bed. 
A)  vasoconstriction. 
B)  vasodilation. 
C)  narrowing of the arteries. 
D)  a reduction in blood flow in that region. 
E)  a decreased amount of blood in the capillaries of that vascular bed.

Question 13

If a molecule of CO2 released into the blood in your left toe is exhaled from your nose, it must pass through all of the following except

Accepted Answer

A)  the pulmonary vein. 
B)  an alveolus. 
C)  the trache
A)  
D)  the right atrium. 
E)  the right ventricle. 
A)  the pulmonary vein. 
B)  an alveolus. 
C)  the trache
A)  
D)  the right atrium. 
E)  the right ventricle.

Question 14

Atmospheric pressure at sea level is equal to a column of 760 mm Hg. Oxygen makes up 21% of the atmosphere by volume. The partial pressure of oxygen (PO2) in such conditions is

Accepted Answer

A)  160 mm Hg. 
B)  16 mm Hg. 
C)  120/75. 
D)  21/760. 
E)  760/21. 
A)  160 mm Hg. 
B)  16 mm Hg. 
C)  120/75. 
D)  21/760. 
E)  760/21.

Question 15

The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in

Accepted Answer

A)  the partial pressure of oxygen. 
B)  the partial pressure of carbon monoxide. 
C)  hemoglobin concentration. 
D)  temperature. 
E)  pH. 
A)  the partial pressure of oxygen. 
B)  the partial pressure of carbon monoxide. 
C)  hemoglobin concentration. 
D)  temperature. 
E)  pH.

Question 16

Gas exchange in the aquatic salamander known as the axolotl is correctly described as

Accepted Answer

A)  active transport to move oxygen into the salamander from the water. 
B)  carrier-mediated transport to move oxygen into the salamander from the water. 
C)  facilitated diffusion of carbon dioxide from the salamander into the water. 
D)  simple diffusion of oxygen into the salamander from the water. 
E)  active transport of carbon dioxide from the salamander into the water. 
A)  active transport to move oxygen into the salamander from the water. 
B)  carrier-mediated transport to move oxygen into the salamander from the water. 
C)  facilitated diffusion of carbon dioxide from the salamander into the water. 
D)  simple diffusion of oxygen into the salamander from the water. 
E)  active transport of carbon dioxide from the salamander into the water.

Question 17

The exhalation of air from human lungs is driven by

Accepted Answer

A)  a decrease in the volume of the thoracic cavity. 
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. 
A)  a decrease in the volume of the thoracic cavity. 
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.

Question 18

The blood pressure is lowest in the

Accepted Answer

A)  aorta. 
B)  arteries. 
C)  arterioles. 
D)  capillaries. 
E)  vena cava. 
A)  aorta. 
B)  arteries. 
C)  arterioles. 
D)  capillaries. 
E)  vena cava.

Question 19

Which of the following develops the greatest pressure on the blood in the mammalian aorta?

Accepted Answer

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 
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

Question 20

The diagnosis of hypertension in adults is based on the

Accepted Answer

A)  measurement of fatty deposits on the endothelium of arteries. 
B)  measurement of the LDL/HDL ratio in peripheral blood. 
C)  percent of blood volume made up of platelets. 
D)  blood pressure being greater than 140 mm Hg systolic and/or >90 diastolic. 
E)  number of leukocytes per mm3 of blood. 
A)  measurement of fatty deposits on the endothelium of arteries. 
B)  measurement of the LDL/HDL ratio in peripheral blood. 
C)  percent of blood volume made up of platelets. 
D)  blood pressure being greater than 140 mm Hg systolic and/or >90 diastolic. 
E)  number of leukocytes per mm3 of blood.

Exam 34: Circulation and Gas Exchange

Gas exchange is more difficult for aquatic animals with gills than for terrestrial animals with lungs because

To become bound to hemoglobin for transport in a mammal, atmospheric molecules of oxygen must cross

An increase from pH 7.2 to pH 7.4 around hemoglobin causes

Which of the following respiratory systems is not closely associated with a blood supply?

Most of the carbon dioxide produced by humans is

Countercurrent exchange is evident in

Air-breathing insects carry out gas exchange

An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, 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

The production of red blood cells is stimulated by

The semilunar valves of the mammalian heart

The velocity of blood flow is the lowest in capillaries because

An increased concentration of nitric oxide within a vascular bed is associated with

If a molecule of CO2 released into the blood in your left toe is exhaled from your nose, it must pass through all of the following except

Atmospheric pressure at sea level is equal to a column of 760 mm Hg. Oxygen makes up 21% of the atmosphere by volume. The partial pressure of oxygen (PO2) in such conditions is

The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in

Gas exchange in the aquatic salamander known as the axolotl is correctly described as

The exhalation of air from human lungs is driven by

The blood pressure is lowest in the

Which of the following develops the greatest pressure on the blood in the mammalian aorta?

The diagnosis of hypertension in adults is based on the

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development, Stem Cells, and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Evolution of Populations

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Species Interactions

Ecosystems and Energy

Global Ecology and Conservation Biology

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