Chapter 39 Review Questions

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 _____. -4 mm Hg -400 mm Hg -82 mm Hg -40 mm Hg

40 mm Hg

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 _____. -4000 mL -1450 mL -5000 mL -4450 mL

5000 mL

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 _____. -160 mm Hg -760 mm Hg -80 mm Hg -380 mm Hg

80 mm Hg

Why do cigarette smokers cough more than nonsmokers? -Cigarette smoking partially paralyzes the muscles in the lungs, resulting in an increased residual volume, and coughing exchanges this "dead air." -By raising the pressure in the lungs, coughing forces more oxygen into the blood. -Cigarette smoke harms the cilia that normally move debris out of the lungs, and coughing is the remaining way to clean the lungs. -The tar in cigarette smoke tends to make alveoli stick together, and coughing separates them.

Cigarette smoke harms the cilia that normally move debris out of the lungs, and coughing is the remaining way to clean the lungs.

How has the avian lung adapted to the metabolic demands of flight? -Airflow through the avian lung is bidirectional like in mammals. -Gas exchange occurs during both inhalation and exhalation. -There is more dead space within the avian lung so that oxygen can be stored for future use. -Countercurrent circulation is present in the avian lung.

Gas exchange occurs during both inhalation and exhalation.

Which part of the diagram shows alveoli? -part A -part B -part C -part D

Part D

Which of the following statements regarding breathing and circulation in insects is false? -The circulatory system of insects is not involved in transporting oxygen. -Insects lose very little water by using a tracheal system to breathe. -Terrestrial animals such as insects spend much more energy than aquatic animals to ventilate their respiratory surfaces. -The tracheal system of insects consists of a series of branching air tubes that extend from the surface to deep inside the body.

Terrestrial animals such as insects spend much more energy than aquatic animals to ventilate their respiratory surfaces.

Which of the following statements comparing respiration in fish and in mammals is correct? -In blood, oxygen is primarily transported by plasma in fish, but by red blood cells in mammals. -The respiratory medium for fish carries more oxygen than the respiratory medium of mammals. -A countercurrent exchange mechanism between the respiratory medium and blood flow is seen in mammals but not in fish. -The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.

The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.

Which of the following statements comparing respiration in fish and in mammals is correct? -The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional. -In blood, oxygen is primarily transported by plasma in fish, but by red blood cells in mammals. -A countercurrent exchange mechanism between the respiratory medium and blood flow is seen in mammals but not in fish. -The respiratory medium for fish carries more oxygen than the respiratory medium of mammals.

The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.

A rabbit taken from a meadow near sea level and moved to a meadow high on a mountainside would have some trouble breathing. Why? -The partial pressure of oxygen in the air at high elevations is lower than at sea level. -The percentage of oxygen in the air at high elevations is lower than at sea level. -The partial pressure of oxygen in the air at high elevations is higher than at sea level. -The percentage of oxygen in the air at high elevations is higher than at sea level.

The partial pressure of oxygen in the air at high elevations is lower than at sea level.

Which of the following statements about fish gills is true? -Because of their efficiency, they only need a small surface area. -Like lungs, they have an exhale/inhale function. -They have a poor blood supply. -They have a surface area that is much greater than the body surface.

They have a surface area that is much greater than the body surface.

The sun shining on a tidal pool during a hot day heats the water. As some water evaporates, the pool becomes saltier, causing _____. -a decrease in its oxygen content -a decrease in the water's density -an increase in its ability to sustain aerobic organisms -an increase in its carbon dioxide content

a decrease in its oxygen content

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? -not enough hemoglobin -hemoglobin -abnormal carbonic anhydrase -abnormally shaped platelets

abnormal carbonic anhydrase

Compared to the vital capacity, how much air can lungs actually hold? -sometimes more -sometimes less -always less -always more

always more

What prompts a newborn baby to start to breathe? -a change in the temperature on the surface of the skin -exposure to air -a decrease in the concentration of oxygen in the baby's blood -an increase in the concentration of carbon dioxide in the baby's blood

an increase in the concentration of carbon dioxide in the baby's blood

Most CO2 is transported to the lungs in which of the following ways? -as carbonic anhydrase -dissolved in the plasma -attached to hemoglobin or as bicarbonate ions -as carboxyl

attached to hemoglobin or as bicarbonate ions

Which of the following animals requires the largest and most complex lungs proportional to its overall body size? -frog -newt -turtle -bear

bear

In the countercurrent exchange system of fish gills, -blood and water are separated by a thick polysaccharide barrier. -blood flow in the gills reverses direction with every heartbeat. -blood and water flow in the same direction. -blood and water flow in opposite directions.

blood and water flow in opposite directions.

Medullary breathing centers directly sense and respond to -blood O2 concentration. -blood pH and O2 concentration. -blood pH and CO2 concentration. -alveolar O2 concentration.

blood pH and CO2 concentration.

A waste product of respiration is -electrons. -glucose. -hydrogen peroxide. -carbon dioxide.

carbon dioxide.

What name is given to the sheet of muscle that helps move air in and out of the lungs? -alveolus -bronchus -trachea -diaphragm

diaphragm

Countercurrent exchange in the fish gill helps to maximize _____. -blood pressure -osmosis -active transport -diffusion

diffusion

The organization of blood and water flow in a fish's gills increases the fish's ability to -extract carbon dioxide from the water. -transport blood throughout the fish's body. -detect toxic materials in the water. -extract oxygen from the water.

extract oxygen from the water.

Which of the following organisms has a respiratory system that does not require assistance from a circulatory system for gas exchange? -carp -grasshopper -crayfish -mouse

grasshopper

Evolutionary movement of aquatic vertebrates to land involved an intermediate individual that - had both gills and lungs. - could fly. - evolved a tracheal system of branching internal tubes. - is called a "podafish."

had both gills and lungs.

Animals that effectively use their body surface for gas exchange must -be terrestrial. -have a low ratio of body surface area to volume. -have a high ratio of body surface area to volume. -have a special kind of hemoglobin.

have a high ratio of body surface area to volume.

The oxygen-carrying component in red blood cells is -bicarbonate ions. -the cell membrane. -hemoglobin. -iron.

hemoglobin.

Compared with the interstitial fluid that bathes active muscle cells, blood reaching these muscle cells in arteries has a _____. -lower pH -lower osmotic pressure -greater bicarbonate concentration -higher PO2

higher PO2

Some human infants, especially those born prematurely, suffer serious respiratory failure because of _____. -mutations in the genes involved in lung formation -the overproduction of surfactants -lung collapse due to inadequate production of surfactant -the sudden change from the uterine environment to the air

lung collapse due to inadequate production of surfactant

What part of the human brain contains the primary breathing control center? -thalamus -neocortex -medulla oblongata -cerebellum

medulla oblongata

The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in _____. -temperature -the partial pressure of oxygen -pH -hemoglobin concentration

pH

The ________ is a passageway shared by both food and air. -nasal cavity -larynx -trachea -pharynx

pharynx

When you exhale, you -remove CO2 from the body. -take up carbon dioxide and release oxygen. -exchange CO2 for O2. -take up oxygen and release carbon dioxide to the blood.

remove CO2 from the body.

When you are breathing normally, exhalation results mainly from -the contraction of the diaphragm. -the contraction of muscles in the chest. -the relaxation of the chest muscles and diaphragm. -low pressure in the lungs.

the relaxation of the chest muscles and diaphragm.

Which of the following contributes to gas exchange in the human fetus? -the lower blood pH of the embryo -the stronger attraction that fetal hemoglobin has for oxygen when compared to adult hemoglobin -the high oxygen levels maintained in the amniotic fluid by the placenta -the lack of turbulence in fetal blood

the stronger attraction that fetal hemoglobin has for oxygen when compared to adult hemoglobin

High-flying birds are able to obtain enough oxygen even when the air is very thin because -their heart can increase or decrease in size as altitude changes. -they have reduced amounts of hemoglobin in their blood. -their mitochondria are more efficient than those of other vertebrates. -they have more efficient lungs than other vertebrates.

they have more efficient lungs than other vertebrates.

Cigarette smoking and secondhand smoke cause cancer due to the -toxins in the smoke. -effects they have on our breathing mechanisms. -resistance they have for products of our immune system. -immunosuppressive effects they display.

toxins in the smoke.

Flying insects typically _____. -switch from diffusion of tracheal gases to active transport during flight -utilize high numbers of mitochondria in flight muscles -decrease metabolism as much as 200-fold during flight -generate fuel molecules from catabolism of carbon dioxide

utilize high numbers of mitochondria in flight muscles

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 _____. -arterial blood would decrease -venous blood would decrease -arterial blood would increase -venous blood would increase

venous blood would decrease

Which of the following is likely to have the lowest concentration of O2? -air -cool salt water -warm salt water -cool fresh water

warm salt water