Question 1

Which of the following best describes the process of ventilation?

Accepted Answer

A)  the movement of oxygen gas through the blood of the circulatory system 
B)  the diffusion of gases into and out of tissues where cellular respiration occurs 
C)  the movement of air through lungs or gills 
D)  the diffusion of gases into and out of the circulatory system 
E)  the movement of carbon dioxide gas through the blood of the circulatory system 
A)  the movement of oxygen gas through the blood of the circulatory system 
B)  the diffusion of gases into and out of tissues where cellular respiration occurs 
C)  the movement of air through lungs or gills 
D)  the diffusion of gases into and out of the circulatory system 
E)  the movement of carbon dioxide gas through the blood of the circulatory system C

Question 2

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 × A × P2 - P1)/D. Natural selection is least likely to act upon which variable in Fick's law?

Accepted Answer

A)  A 
B)  D 
C)  P2 - P1  
D)  k 
A)  A 
B)  D 
C)  P2 - P1  
D)  k D

Question 3

In a cross section through an artery and vein running parallel in your leg, which would be the artery?

Accepted Answer

A)  The vessel with more muscle tissue in the wall. 
B)  The vessel lined with endothelium. 
C)  The vessel with the largest interior diameter. 
D)  The vessel with valves to prevent backflow. 
E)  All of the above answers apply. 
A)  The vessel with more muscle tissue in the wall. 
B)  The vessel lined with endothelium. 
C)  The vessel with the largest interior diameter. 
D)  The vessel with valves to prevent backflow. 
E)  All of the above answers apply. A

Question 4

Which of the four muscular chambers of the human heart directly propels blood into the pulmonary circulation?

Accepted Answer

A)  left ventricle 
B)  right atrium 
C)  right ventricle 
D)  left atrium 
A)  left ventricle 
B)  right atrium 
C)  right ventricle 
D)  left atrium

Question 5

Insect trachea come in direct contact with the internal organs to which they deliver oxygen. What parameter of Fick's Law does this optimize?

Accepted Answer

A)  A 
B)  P 
C)  K 
D)  D 
A)  A 
B)  P 
C)  K 
D)  D

Question 6

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?

Accepted Answer

A)  The amount of oxygen in arterial blood would increase. 
B)  The amount of oxygen in venous blood would increase. 
C)  The amount of oxygen in venous blood would decrease. 
D)  The amount of oxygen in arterial blood would decrease. 
E)  More than one of the above is true. 
A)  The amount of oxygen in arterial blood would increase. 
B)  The amount of oxygen in venous blood would increase. 
C)  The amount of oxygen in venous blood would decrease. 
D)  The amount of oxygen in arterial blood would decrease. 
E)  More than one of the above is true.

Question 7

What is the rate of diffusion in the gas- exchange organ of an air- breathing animal where the area for gas exchange in the lung is 200 mm2, the diffusion constant is 0.08, 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 mmHg, and the thickness of the gas exchange membrane is 0.001 mm?

Accepted Answer

A)  00032 
B)  800,000 
C)  125 
D)  10,000,000 
A)  00032 
B)  800,000 
C)  125 
D)  10,000,000

Question 8

What is the main difference between respiration in terrestrial insects and in terrestrial vertebrates?

Accepted Answer

A)  Insects rely on the blood in their circulatory system to deliver oxygen from the air to their tissues, whereas terrestrial vertebrates rely on their lungs to deliver oxygen in air to their tissues. 
B)  Insects have a lower metabolic rate than terrestrial vertebrates do, so they tend to rely more heavily on their circulatory system than their tracheal system for oxygen transport. 
C)  Insects rely on their tracheal system to deliver oxygen in air to their tissues, whereas terrestrial vertebrates rely on their lungs to deliver oxygen to their tissues through the blood in their circulatory system. 
D)  Insects use their tracheal system to transfer oxygen from air into blood, whereas terrestrial vertebrates use their lungs to transfer oxygen from air into blood. 
A)  Insects rely on the blood in their circulatory system to deliver oxygen from the air to their tissues, whereas terrestrial vertebrates rely on their lungs to deliver oxygen in air to their tissues. 
B)  Insects have a lower metabolic rate than terrestrial vertebrates do, so they tend to rely more heavily on their circulatory system than their tracheal system for oxygen transport. 
C)  Insects rely on their tracheal system to deliver oxygen in air to their tissues, whereas terrestrial vertebrates rely on their lungs to deliver oxygen to their tissues through the blood in their circulatory system. 
D)  Insects use their tracheal system to transfer oxygen from air into blood, whereas terrestrial vertebrates use their lungs to transfer oxygen from air into blood.

Question 9

If other factors are equal, which of the following environments would have the highest level of dissolved oxygen?

Accepted Answer

A)  warm, fresh water at high elevation 
B)  cool, fresh water at high elevation 
C)  cool, salty water at low elevation 
D)  cool, fresh water at low elevation 
E)  warm, salty water at low elevation 
A)  warm, fresh water at high elevation 
B)  cool, fresh water at high elevation 
C)  cool, salty water at low elevation 
D)  cool, fresh water at low elevation 
E)  warm, salty water at low elevation

Question 10

Carbon dioxide levels in the blood and in cerebrospinal fluid affect the pH of these fluids. Which of the following mechanisms does an organism use to sense a disturbance in gas?

Accepted Answer

A)  Neurons in contact with cerebrospinal fluid monitor pH and use this measure to control breathing. 
B)  Stretch receptors in the lungs cause the medulla oblongata to speed up or slow breathing. 
C)  The brain alters the pH of the cerebrospinal fluid to force the animal to retain more or less carbon dioxide. 
D)  The medulla oblongata is able to control the concentration of bicarbonate ions in the blood. 
E)  The brain directly measures and monitors oxygen levels and causes breathing changes accordingly. 
A)  Neurons in contact with cerebrospinal fluid monitor pH and use this measure to control breathing. 
B)  Stretch receptors in the lungs cause the medulla oblongata to speed up or slow breathing. 
C)  The brain alters the pH of the cerebrospinal fluid to force the animal to retain more or less carbon dioxide. 
D)  The medulla oblongata is able to control the concentration of bicarbonate ions in the blood. 
E)  The brain directly measures and monitors oxygen levels and causes breathing changes accordingly.

Question 11

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?

Accepted Answer

A)  Relative to their surface area, the young have more body volume in which they can store oxygen for long periods of time. 
B)  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. 
C)  The young have a higher basal metabolic rate. 
D)  Relative to their volume, the young have more surface area across which they can transport all the oxygen they need. 
A)  Relative to their surface area, the young have more body volume in which they can store oxygen for long periods of time. 
B)  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. 
C)  The young have a higher basal metabolic rate. 
D)  Relative to their volume, the young have more surface area across which they can transport all the oxygen they need.

Question 12

In what way does hemoglobin act as a buffer against changes in blood pH?

Accepted Answer

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 removes excess protons from the red blood cells so that they can be excreted through the kidneys. 
D)  Hemoglobin produces protons or hydroxide ions as needed to alter the blood pH. 
E)  All of the above answers apply. 
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 removes excess protons from the red blood cells so that they can be excreted through the kidneys. 
D)  Hemoglobin produces protons or hydroxide ions as needed to alter the blood pH. 
E)  All of the above answers apply.

Question 13

Marine crabs have internal gills covered by an exoskeleton, and, because their whole body is covered by exoskeleton, they cannot expand their body enough to generate much negative pressure within the gill chambers to draw water in over their gills. Which of the following would serve to increase the efficiency of gas exchange by marine crabs?

Accepted Answer

A)  a countercurrent exchange system 
B)  oxygen- carrying molecules in the blood 
C)  movement of limbs or other structures to create a current over the gills 
D)  all of the above 
E)  only B and C 
A)  a countercurrent exchange system 
B)  oxygen- carrying molecules in the blood 
C)  movement of limbs or other structures to create a current over the gills 
D)  all of the above 
E)  only B and C

Question 14

An animal has a cardiac output of 40 mL/min and a stroke volume of 5 mL. What is its heart rate?

Accepted Answer

A)  12.5 beats/minute 
B)  8 beats/minute 
C)  200 beats/minute 
D)  Heart rate cannot be determined with only these two variables. 
A)  12.5 beats/minute 
B)  8 beats/minute 
C)  200 beats/minute 
D)  Heart rate cannot be determined with only these two variables.

Question 15

Which of the following is NOT a feature of gas exchange in the respiratory system of birds?

Accepted Answer

A)  The flow of air through the lungs is one way. 
B)  Gas exchange occurs during both inhalation and exhalation. 
C)  The exchange of gases between parabronchi and blood is in a countercurrent direction. 
D)  The dead space within the respiratory system is small compared to that in mammals. 
A)  The flow of air through the lungs is one way. 
B)  Gas exchange occurs during both inhalation and exhalation. 
C)  The exchange of gases between parabronchi and blood is in a countercurrent direction. 
D)  The dead space within the respiratory system is small compared to that in mammals.

Question 16

Which of the following is the normal sequence of signal conduction in the human heart?

Accepted Answer

A)  neural and chemical messengers -AV node -atria -SA node -ventricles 
B)  neural but not chemical messengers -AV node -ventricles -SA node - atria 
C)  neural and chemical messengers -ventricles -SA node -atria -AV node 
D)  neural and chemical messengers -SA node -atria -AV node -ventricles 
E)  chemical but not neural messengers -atria -SA node -ventricles -AV node 
A)  neural and chemical messengers -AV node -atria -SA node -ventricles 
B)  neural but not chemical messengers -AV node -ventricles -SA node - atria 
C)  neural and chemical messengers -ventricles -SA node -atria -AV node 
D)  neural and chemical messengers -SA node -atria -AV node -ventricles 
E)  chemical but not neural messengers -atria -SA node -ventricles -AV node

Question 17

Where does the blood within the pulmonary vein travel next?

Accepted Answer

A)  left atrium of the heart 
B)  pulmonary artery 
C)  alveolar capillaries 
D)  right atrium of the heart 
A)  left atrium of the heart 
B)  pulmonary artery 
C)  alveolar capillaries 
D)  right atrium of the heart

Question 18

Which of the following mechanisms play a role in regulating heart rate?
Which of the following mechanisms play a role in regulating heart rate?

Accepted Answer

A)  chemical messengers in the blood, such as epinephrine 
B)  nerves originating from the medulla lower part of the brain) 
C)  pacemaker cells within the heart 
D)  all of the above A to 
C)  
E)  only A and C 
A)  chemical messengers in the blood, such as epinephrine 
B)  nerves originating from the medulla lower part of the brain) 
C)  pacemaker cells within the heart 
D)  all of the above A to 
C)  
E)  only A and C

Question 19

Baroreceptors are specialized pressure- sensing nerve cells that are important in circulatory homeostasis. Where are these nerve cells located in humans?

Accepted Answer

A)  cells in brain 
B)  arteries entering the neck region 
C)  arteries leaving the heart 
D)  all of the above 
E)  only B and C 
A)  cells in brain 
B)  arteries entering the neck region 
C)  arteries leaving the heart 
D)  all of the above 
E)  only B and C

Question 20

The air pressure in Denver, Colorado, is about 83% of the air pressure in Miami Beach, which is about sea level. Given that the air pressure in Miami Beach is 760 mm Hg and oxygen makes up 21% of the air in Miami Beach, what is the percentage of oxygen and the partial pressure of oxygen in Denver, respectively?

Accepted Answer

A)  17.4%; 21 mm Hg 
B)  21%; 21 mm Hg 
C)  21%; 132 mm Hg 
D)  17.4%; 132 mm Hg 
A)  17.4%; 21 mm Hg 
B)  21%; 21 mm Hg 
C)  21%; 132 mm Hg 
D)  17.4%; 132 mm Hg

Exam 42: Gas Exchange and Circulation

Which of the following best describes the process of ventilation?

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 × A × P2 - P1)/D. Natural selection is least likely to act upon which variable in Fick's law?

In a cross section through an artery and vein running parallel in your leg, which would be the artery?

Which of the four muscular chambers of the human heart directly propels blood into the pulmonary circulation?

Insect trachea come in direct contact with the internal organs to which they deliver oxygen. What parameter of Fick's Law does this optimize?

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?

What is the main difference between respiration in terrestrial insects and in terrestrial vertebrates?

If other factors are equal, which of the following environments would have the highest level of dissolved oxygen?

Carbon dioxide levels in the blood and in cerebrospinal fluid affect the pH of these fluids. Which of the following mechanisms does an organism use to sense a disturbance in gas?

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?

In what way does hemoglobin act as a buffer against changes in blood pH?

An animal has a cardiac output of 40 mL/min and a stroke volume of 5 mL. What is its heart rate?

Which of the following is NOT a feature of gas exchange in the respiratory system of birds?

Which of the following is the normal sequence of signal conduction in the human heart?

Where does the blood within the pulmonary vein travel next?

Which of the following mechanisms play a role in regulating heart rate? Which of the following mechanisms play a role in regulating heart rate?

Baroreceptors are specialized pressure- sensing nerve cells that are important in circulatory homeostasis. Where are these nerve cells located in humans?

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Lipids, Membranes, and the First Cells

Inside the Cell

Energy and Enzymes

Cellular Respiration and Fermentation

Photosynthesis

Cellcell Interactions

The Cell Cycle

Meiosis

Mendel and the Gene

Dna and the Gene: Synthesis and Repair

How Genes Work

Transcription, Rna Processing, and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

The Molecular Revolution: Biotechnology and Beyond

Gene Structure and Development

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Algae and Land Plants

Fungi

An Introduction to Animals

Protostome Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Sensory Systems, Signals, and Responses

Plant Reproduction and Development

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Animal Nervous Systems

Animal Sensory Systems

Animal Movement

Chemical Signals in Animals

Animal Reproduction and Development

The Immune System in Animals

An Introduction to Ecology

Behavioural Ecology

Population Ecology

Community Ecology

Ecosystems and Global Ecology

Biodiversity and Conservation Biology

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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 × A × P₂- P₁)/D. Natural selection is least likely to act upon which variable in Fick's law?