Deck 46: Gas Exchange

Question 1

The process of gas exchange in parabronchi is similar to:

A) osmosis in spiracles.
B) respiration in tracheal tubes.
C) concurrent exchange in gills.
D) diffusion in small animals.
E) countercurrent exchange in gills.

Answer 1

E

Question 2

The countercurrent exchange system found in fish gills maximizes gas exchange efficiency by:

A) producing rapid water flows across the gill surface.
B) allowing water and blood to come in direct contact to maximize oxygen exchange.
C) having a high concentration gradient of oxygen at the start of the capillaries.
D) maintaining a high concentration gradient of oxygen along the entire length of capillaries.
E) decreasing the oxygen content of the blood leaving the gill filaments.

Answer 2

D

Question 3

The ventilation of insect tracheal tubes is dependent upon the presence of:

A) pores.
B) alveoli.
C) gills.
D) spiracles.
E) opercula.

Answer 3

D

Question 4

A respiratory system is needed if an organism is too ____ to rely on the diffusion of gases through the body's tissues.

A) small
B) long
C) thick
D) thin
E) round

Question 5

Mitochondria use respired oxygen as an electron acceptor in the process known as:

A) pulmonary ventilation.
B) cellular respiration.
C) external respiration.
D) internal respiration.
E) anaerobic respiration.

Question 6

Why do land dwelling insects drown when they are in water?

A) Their lungs fill with water.
B) Their lungs are functioning too fast to sustain life.
C) They cannot respire across their body surface.
D) They are unable to ventilate because their spiracles are underwater.
E) Their gills are too moist.

Question 7

In the process of organismic respiration:

A) oxygen is extracted from the environment by the organism and delivered to its cells.
B) the citric acid cycle takes place in the cells.
C) carbohydrates are broken down and electrons are transferred to oxygen.
D) there is an accumulation of lactic acid in the tissues due to the absence of oxygen.
E) carbon dioxide is produced in the Krebs cycle.

Question 8

In fish, blood flows in a direction opposite to the flow of water over the gills in a process known as:

A) concurrent exchange.
B) countercurrent exchange.
C) crosscurrent exchange.
D) exhalation.
E) diffusion.

Question 9

Clams and other bivalves typically have:

A) dermal gills.
B) gills adapted for trapping food.
C) an operculum.
D) book lungs.
E) swim bladders.

Question 10

____ have the most efficient respiratory system of any living vertebrate.

A) Amphibians
B) Birds
C) Mammals
D) Fish
E) Nonavian reptiles

Question 11

To facilitate respiration, birds have extensions of their lungs called ____, which reach into all parts of their bodies.

A) tracheal tubes
B) spiracles
C) air bladders
D) parabronchi
E) air sacs

Question 12

If mitochondria were deprived of oxygen:

A) cellular respiration would cease.
B) ATP synthesis would cease.
C) cells would eventually die.
D) cellular respiration and ATP synthesis would cease.
E) cellular respiration and ATP synthesis would cease and the cells would eventually die.

Question 13

Which of the following sequences correctly describes the movement of air in a bird's respiratory system?

A) lungs; anterior air sacs; posterior air sacs
B) anterior air sacs; posterior air sac; lungs
C) posterior air sacs; lungs; anterior air sacs
D) lungs; posterior air sacs; anterior air sacs
E) anterior air sacs; lungs; posterior air sacs

Question 14

Some amphibians:

A) may exchange gases across their body surfaces.
B) all have fairly simple, book lungs.
C) all have gills and swim bladders, homologous to those found in fishes.
D) are characterized by having parabronchi across which most of the gas exchange occurs.
E) have a large oxygen demand that is met by using a countercurrent gas exchange mechanism.

Question 15

Figure 46-1 Refer to the accompanying figure. Which two figures in the accompanying illustration represent inhalation steps of the respiratory cycle?

A) 1 and 3
B) 1 and 2
C) 2 and 3
D) 2 and 4
E) 3 and 4

Question 16

Fish can control buoyancy by:

A) holding air in their lungs.
B) expelling air from their lungs.
C) facilitating swift operculum movement.
D) adjusting the amount of gas in their swim bladders.
E) inflating the chambers of their tracheae.

Question 17

The exchange of gases between an organism and its environment is known as:

A) exhalation.
B) aeration.
C) inhalation.
D) respiration.
E) ventilation.

Question 18

Figure 46-1 Refer to the accompanying figure. Place figures 1-4 in the correct order to represent the two-cycle breathing process of birds.

A) 1 → 2 → 3 → 4
B) 2 → 3 → 4 → 1
C) 2 → 3 → 1 → 4
D) 3 → 2 → 1 → 4
E) 4 → 3 → 2 → 1

Question 19

Parabronchi are characteristic of:

A) insects.
B) spiders.
C) mollusks.
D) birds.
E) mammals.

Question 20

Which of the following is a disadvantage of gas exchange in water, as compared to gas exchange in air?

A) Air is less dense than water.
B) Air contains a higher concentration of oxygen.
C) Less energy is needed to move air over a gas exchange surface.
D) Oxygen diffuses more slowly through air than water.
E) Air is less viscous than water.

Question 21

The volume of air remaining in the lungs after maximal expiration is the:

A) vital capacity.
B) tidal volume.
C) tidal capacity.
D) residual capacity.
E) residual volume.

Question 22

Hemocyanin:

A) combines irreversibly with oxygen for transport within the body of various organisms.
B) is bright red in color when combined with oxygen.
C) has an iron-porphyrin group that is responsible for oxygen transport.
D) is a respiratory pigment found in the blood of some invertebrate and vertebrate species.
E) is a respiratory pigment that is colorless when deoxygenated.

Question 23

The percent oxygen saturation of hemoglobin is highest in the:

A) tissues where oxygen concentration is lowest.
B) tissues where oxygen concentration is highest.
C) venules where oxygen concentration is lowest.
D) pulmonary capillaries where oxygen concentration is lowest.
E) pulmonary capillaries where oxygen concentration is highest.

Question 24

Figure 46-4 Oxygen-hemoglobin dissociation curves at three different pH levels
The phenomenon illustrated in the accompanying figure is known as:

A) carbon dioxide unloading.
B) the Bohr effect.
C) hemoglobin transportation.
D) chloride shift.
E) residual capacity.

Question 25

Figure 46-3 Refer to the accompanying figure. Which statement is accurate?

A) CO₂ will diffuse from the alveoli into the capillaries.
B) CO₂ will diffuse from the capillaries into the tissues.
C) O₂ will diffuse from the capillaries in the tissues to the capillaries in the lung.
D) O₂ will diffuse from the alveoli into the capillaries.
E) O₂ will diffuse from the tissues into the capillaries.

Question 26

Figure 46-2 Refer to the accompanying figure. Which of these lungs would be found in reptiles?

A) 1 only
B) 2 only
C) 3 only
D) 4 only
E) both 1 and 2

Question 27

Which of the following occurs during forced expiration?

A) The alveoli inflate.
B) The ribs move upward.
C) The internal intercostal muscles contract.
D) The floor of the thoracic cavity moves downward.
E) The pressure increases in the thoracic cavity.

Question 28

The maximum amount of air a person can exhale is called:

A) vital capacity.
B) tidal volume.
C) tidal capacity
D) residual capacity.
E) residual volume

Question 29

The amount of air being moved with each ventilation is referred to as:

A) vital capacity.
B) tidal volume.
C) residual capacity.
D) the Bohr effect.
E) hyperventilation.

Question 30

Figure 46-2 Refer to the accompanying figure. Which of these lungs would be best for an animal that is fairly active?

A) 1
B) 2
C) 3
D) 4
E) Any of these.

Question 31

Fick's law states that:

A) the amount of gas diffusing across a membrane depends on differences in partial pressure.
B) the total pressure of a mixture of gases is the sum of the pressures of the individual gases.
C) the dissociation of oxygen from hemoglobin depends on the pH of the environment.
D) as oxygen concentration increases, there is an increase in the amount of hemoglobin produced.
E) the size of an animal varies inversely to the amount of diffusion across its respiratory membranes.

Question 32

Figure 46-1 Refer to the accompanying figure. The structures receiving air in figure 1 are known as:

A) anterior air sacs.
B) parabronchi.
C) spiracles.
D) alveoli.
E) tracheae.

Question 33

Which of the following is typically used to measure the functional capacity of the lungs?

A) vital capacity
B) tidal volume
C) tidal capacity
D) residual capacity
E) residual volume

Question 34

Both aquatic and terrestrial organisms must have ____ across which gas exchange can take place.

A) a respiratory system
B) tracheal tubes
C) gills and lungs
D) stratified squamous epithelial tissue
E) a moist surface

Question 35

The most common respiratory pigments in animals are:

A) myoglobin and hemocyanin.
B) myoglobin and hemoglobin.
C) hemocyanin and hemoglobin.
D) mucus and hemoglobin.
E) pulmonary surfactant and myoglobin.

Question 36

During respiratory exchange, carbon dioxide moves from the blood into the alveoli due to:

A) the presence of a permease, which removes carbon dioxide from the capillaries.
B) potassium cotransport.
C) diffusion down a concentration gradient.
D) the air pressure of dissolved oxygen, which forces it out.
E) the contraction of the diaphragm, which creates a vacuum that pulls it out.

Question 37

Which of the following best defines the Bohr effect?

A) The amount of a gas that diffuses across a membrane depends on the differences in the gas' partial pressure.
B) The ability of hemoglobin to bind oxygen depends on the partial pressure of oxygen.
C) In a mixture of gases, the total pressure of the mixture is the sum of the pressures of the individual gases.
D) pH causes a displacement of the oxygen-hemoglobin dissociation curve.
E) As the concentration of chloride ions increases, the ability of hemoglobin to bind carbon dioxide decreases.

Question 38

Dalton's Law states that:

A) the amount of a gas that diffuses across a membrane depends on the differences in the gas' partial pressure.
B) the ability of hemoglobin to bind oxygen depends on the partial pressure of oxygen.
C) in a mixture of gases, the total pressure of the mixture is the sum of the pressures of the individual gases.
D) pH causes a displacement of the oxygen-hemoglobin dissociation curve.
E) as the concentration of chloride ions increases, the ability of hemoglobin to bind carbon dioxide decreases.

Question 39

Figure 46-2 Refer to the accompanying figure. Which of these lungs would have the greatest surface area?

A) 1
B) 2
C) 3
D) 4
E) All have equal surface area.

Question 40

Figure 46-3 Refer to the accompanying figure. Which statement is FALSE?

A) The of the air in the alveoli must be greater than 100 mm Hg.
B) The in the tissues must be less than 100 mm Hg.
C) The of the air in the alveoli must be less than 40 mm Hg.
D) The in the tissues must be greater than 40 mm Hg.
E) The in the tissues must be equal to the in the tissues.

Question 41

Which of the following areas of the respiratory tract is lined with a single layer of epithelial cells?

A) nasal cavity
B) larynx
C) trachea
D) bronchi
E) alveoli

Question 42

Which statement about the regulation of respiration is FALSE?

A) Respiratory centers in the medulla control the transition from inspiration to expiration.
B) Carbon dioxide concentration is the most important chemical stimulus for regulating respiratory rate.
C) Chemoreceptors in the walls of various arteries are sensitive to carbon dioxide levels in the blood.
D) A group of neurons in the ventral medulla only become active when we need to breathe forcefully.
E) Chemoreceptors may be sensitive to oxygen, carbon dioxide, and/or hydrogen ion concentration.

Question 43

The smallest branches of the respiratory tree are the:

A) pharynx.
B) tracheae.
C) bronchial tubes.
D) bronchioles.
E) bronchi.

Question 44

The ability of oxygen to combine with and detach from hemoglobin is influenced by which of the following factors?

A) percent oxygen saturation
B) humidity
C) oxygen concentration
D) tidal volume
E) partial pressure

Question 45

Cilia lining the respiratory tubes beat mucus upward in order to:

A) moisten the bronchioles.
B) conduct the mucus that contains particles to the pharynx and away from the lungs.
C) provide mucus to the lungs to prevent them from dehydrating.
D) lubricate the throat for easier swallowing.
E) promote gas exchange by providing mucus for the respiratory surfaces.

Question 46

The film of fluid in the pleural cavity functions to:

A) nourish the lungs.
B) rehydrate the lungs.
C) provide lubrication between the lungs and thoracic wall.
D) trap bacteria that may enter the lungs.
E) inflate the lungs.

Question 47

In the chloride shift, ____ move into RBCs to replace the ____ that move out.

A) oxygen molecules; chloride ions
B) carbon dioxide molecules; chloride ions
C) bicarbonate ions; chloride ions
D) chloride ions; oxygen molecules
E) chloride ions; bicarbonate ions

Question 48

Decompression sickness is caused by:

A) dissolved gases coming out of solution and forming gas bubbles.
B) the concentration of hemoglobin dropping markedly.
C) chloride ions precipitating from solution.
D) the pH of the blood rising too rapidly.
E) carbonic anhydrase being inhibited.

Question 49

Oxygen concentration generally plays an important role in regulating respiration:

A) all the time.
B) never.
C) only when the carbon dioxide concentration falls markedly.
D) only when the oxygen concentration falls markedly.
E) only when the pH falls markedly.

Question 50

The voice box is also referred to as the:

A) larynx.
B) nasal cavity.
C) epiglottis.
D) pharynx.
E) trachea.

Question 51

During swallowing, ____ closes off the ____ so food cannot enter the lower airway.

A) the pleural membrane; trachea
B) cartilage; larynx
C) the pharynx; esophagus
D) the Adam's apple; trachea
E) the epiglottis; larynx

Question 52

The pleural cavity is located:

A) between the pleural membranes.
B) inside the innermost pleural membrane.
C) outside the outermost pleural membrane.
D) between the right lung and the left lung.
E) within the bronchioles.

Question 53

When drinking water at a party you sneeze and water comes out of your nose. Why did this happen?

A) The epiglottis did not close.
B) The glottis did not close.
C) The pharynx and nasal cavity were connected.
D) The tongue blocked the pharynx.
E) The water was carbonated.

Question 54

Asian pearl divers hyperventilate in order to reduce the ____ concentration in the blood.

A) oxygen
B) hydrogen ion
C) carbon dioxide
D) chloride ion
E) hemoglobin

Question 55

Respiratory acidosis results when ____ are produced more rapidly than they are removed.

A) oxygen molecules
B) carbon dioxide molecules
C) chloride ions
D) hydrogen ions
E) carbonic anhydrase molecules

Question 56

Most of the carbon dioxide in the blood is transported:

A) by being dissolved in plasma.
B) as bicarbonate ions.
C) by hemoglobin.
D) as carbonic anhydrase.
E) as carbonic acid.

Question 57

When chemoreceptors detect a slight decrease in pH, this means that ____ concentrations have increased, and the breathing rate must ____.

A) carbon dioxide; increase
B) carbon dioxide; decrease
C) oxygen; increase
D) oxygen; decrease
E) chloride; decrease

Question 58

Carbonic anhydrase in red blood cells:

A) removes oxygen from the erythrocyte.
B) carries carbon dioxide in the erythrocyte.
C) converts carbon dioxide to carbonic acid.
D) increases the pH of the blood.
E) increases the permeability of the capillary to carbon dioxide.

Question 59

What will happen if a carbonic anhydrase inhibitor is added to blood?

A) The level of CO₂ in the blood will increase.
B) The level of CO₂ in the blood will decrease.
C) The level of CO₂ in the blood will remain the same.
D) The pH of the blood will remain the same.
E) The pH of the blood will decrease.

Question 60

What happens at higher altitudes?

A) The concentration of oxygen decreases.
B) The concentration of carbon dioxide increases.
C) The partial pressure of oxygen decreases.
D) The partial pressure of carbon dioxide increases.
E) There is no change in the concentration or partial pressures of atmospheric gases.

Question 61

The efficient exchange of gases in gills is an example of countercurrent exchange .

Question 62

You have a significant reduction in the amount of pulmonary surfactant. What is the likely effect?

A) The risk of bacterial infection will increase.
B) The risk of having chronic obstructive pulmonary disease will increase.
C) The bronchioles will constrict, which will increase airway resistance.
D) The lungs will be difficult to inflate.
E) Gas exchange cannot occur.

Question 63

During forced inhalation, the ____ intercostal muscles contract, moving ____ upward.

A) internal; the diaphragm
B) internal; the ribs
C) external; the diaphragm
D) external; the ribs
E) external; both the diaphragm and the ribs

Question 64

Arrange the structures through which air passes upon entering the body in the proper sequence.
1) alveoli
2) bronchi
3) larynx
4) bronchioles
5) pharynx
6) trachea

A) 5 → 3 → 6 → 2 → 4 → 1
B) 3 → 5 → 2 → 6 → 1 → 4
C) 2 → 4 → 3 → 5 → 6 → 1
D) 3 → 6 → 5 → 2 → 4 → 1
E) 5 → 6 → 3 → 4 → 2 → 1

Question 65

During exhalation, air moves from the bronchi directly into the alveoli .

Question 66

The parabronchi of birds are open at both ends .

Question 67

During inspiration, the diaphragm ____ and ____ the volume of the thoracic cavity, causing air to flow ____.

A) relaxes; increases; inward
B) contracts; increases; inward
C) relaxes; decreases; outward
D) relaxes; decreases; inward
E) contracts; decreases; inward

Question 68

Dalton's law of partial pressures states that the total pressure of a mixture of gases is equal to the sum of the pressures of the individual gases.

Question 69

Which of the following occurs in pulmonary emphysema?

A) The alveoli lose their elasticity.
B) The surface area of the lung is greatly decreased.
C) Walls between adjacent alveoli become reinforced.
D) The heart becomes enlarged from pressure.
E) Fresh air accumulates in the lungs because it cannot be properly inhaled.

Question 70

Identify a respiratory pigment, and then describe its structure and how this relates to its function.

Question 71

Compare and contrast the advantages and disadvantages of gas exchange in terrestrial and aquatic environments.

Question 72

Tracheal tubes and spiracles are characteristically found in annelids .

Question 73

The single most preventable cause of disease in the United States is:

A) alcohol use.
B) tobacco use.
C) automobile accidents.
D) suicide.
E) homicide.

Question 74

Gases move freely across the walls of the bronchioles into the capillaries that surround them.

Question 75

During inhalation, the diaphragm moves upward .

Question 76

The swim bladders of fishes function primarily in ventilation .

Question 77

Vocal cords are located in the larynx.

Question 78

During inhalation, air moves from the pharynx directly into the trachea .

Question 79

Pulmonary surfactant functions by:

A) increasing the cohesive forces of water molecules.
B) increasing the surface tension of water.
C) moving water across respiratory surfaces.
D) preventing the alveoli from expanding.
E) increasing the energy required to stretch the lungs.

Question 80

Identify and briefly explain two adaptations of diving marine mammals, such as seals and dolphins.