Ch. 48 The Respiratory System
Outline the movement of air in the respiratory system of birds starting with an inhalation and ending with its exhalation.
1) air enters posterior sacs 2) air moves to lungs 3) air enters anterior sacs 4) air exits the body
Rank the efficiency of these respiratory systems, starting with least efficient on top and ending with most efficient at the bottom.
1) amphibian 2) reptile 3) birds and mammals 4) fish
Order the following structures in the mammalian respiratory system according to when the air passes through them, from first to last.
1) nose 2) larynx 3) trachea 4) bronchi 5) bronchioles
Which of the following represents the partial pressure of oxygen at sea level?
160 mmHg
Under normal conditions, the percent oxyhemoglobin saturation in the tissues is 75%, therefore
22% of the oxygen is unloaded in the tissues.
Under normal conditions, the percent oxyhemoglobin saturation in the tissues is 75%, therefore
22% of the oxygen is uploaded in the tissues.
The maximum O2 per liter in blood plasma is ______ ml.
3
The maximum O2 per liter in blood plasma is _______ ml.
3
Blood plasma can contain a maximum of
3ml of O2 per liter
What is the maximum number of oxygen molecules that can bind to a single molecules of hemoglobin?
4
What is the number of oxygen molecules that can bind to a single molecule of hemoglobin?
4
In mammals, blood returning from the systemic circulation (depleted in oxygen) typically has an oxygen partial pressure of ____ mm Hg.
40
Oxygen in the mitochondria is used in the formation of which of the following compounds?
ATP
In fishes, where does water go after it is inhaled?
Across and through the gills
Which of the following are the two main causes of lung cancer?
Air pollution Cigarette smoking
Which of the following are common causes of COPDs?
Allergens Air pollution Airborne irritants Cigarette smoking
Which of the following animals can employ cutaneous respiration?
Amphibians Some turtles
Carbon dioxide is released from human tissues as a waste product. In which of the following ways can it be transported to the lungs?
As bicarbonate ions Dissolved in solution inside erythrocytes Bound to hemoglobin Dissolved in solution in plasma
Why have most multicellular organisms evolved structural adaptations which maximize gas diffusion from the environment?
Because direct diffusion of oxygen into each cell can provide enough oxygen only over distances under 0.5 mm.
Why do multicellular organisms have to rely on specialized systems for transport and exchange of gases?
Because most of their cells are not in direct contract with the external environment.
Why does myoglobin release its oxygen reserve only after hemoglobin oxygen reserves have been depleted?
Because myoglobin has higher affinity for oxygen than hemoglobin
Which of the following statements about Earth's air is true?
Because of gravity, air exerts a pressure on objects below it.
Why can the two pleural membranes couple the lungs to the thoracic cavity?
Because the pleural cavity is very small and filled with fluid.
When a fish is taken out of water, its gills can no longer function properly in gas exchange. Why is this the case?
Because they need to be supported by water and collapse in air
Where are the gills of bony fish located?
Between the buccal and the opercular cavities
What are the effects of emphysema?
Breathing takes significantly more energy Air passages constrict so the person cannot fully exhale Lungs become less elastic
How do lungs and gills maximize the exchange of gases between the external environment and the internal fluid of animals?
By decreasing the distance across which gases must diffuse By increasing surface area available for exchange
Which of the following are ways in which the rate of diffusion of a gas across a membrane can be increased?
By increasing the surface area of the membrane. By decreasing the distance across which diffusion is occurring.
How do gases move across the plasma membrane and other cellular membranes?
By passive diffusion
A general acronym that refers to any disorder that obstructs airflow in the lungs on a long-term basis is ______.
COPD
Which enzyme catalyzes the conversion of carbon dioxide into carbonic acid in the cytoplasm of red blood cells?
Carbonic anhydrase
How is ventilation in mammalian lungs controlled?
Cells in the brainstem detect concentrations of molecules and ions in the blood and adjust muscle contractions accordingly.
Why does countercurrent flow maximize oxygen exchange in internal fish gills?
Countercurrent ensures that there is an oxygen gradient along the entire length of the gill lamellae.
What is the mechanism, which maximizes gas exchange by the movement of water over the gills in the opposite direction to the flow of blood called?
Countercurrent flow
Which of the following organisms protect their gills in branchial chamber?
Crustaceans Mollusks
Which of the following organisms protect their gills in branchial chambers?
Crustaceans Mollusks
Of the following types of gas exchanges, which is least efficient?
Cutaneous respiration
Evolutionary strategies for maximizing gas diffusion include which of the following?
Decreasing distance for gases to travel Increasing the surface area for diffusion Increasing oxygen concentration difference
Which of the following are the major chronic obstructive pulmonary diseases?
Emphysema Asthma Chronic bronchitis
Which of the following are part of hemoglobin?
Fe atom Heme
Evolutionary strategies for maximizing gas diffusion include which of the following?
Increasing the surface area for diffusion Decreasing distance for gases to travel Increasing oxygen concentration difference
Most different organisms with the types of respiratory organs they employ.
Insects - Tracheae Echinoderms - Papulae Fish - Complex gills Adult amphibians - Skin and lungs Birds - Lungs
How does the formation of carbonic acid in red blood cells help an animal maintain homeostasis?
It lowers the concentration of CO2 in blood allowing more CO2 to diffuse from surrounding tissues.
In a person with hypothermia (clinically low body temperature), what do you think would happen to the oxygen-binding affinity of hemoglobin?
It would increase
Which of the following conditions provides the most powerful stimulus for breathing in mammals?
Low pH; high CO2
What are the effects of emphysema?
Lungs become less elastic Air passages constrict so the person cannot fully exhale Breathing takes significantly more energy
Match the gas in air with its approximate concentration.
Nitrogen - 78% Oxygen - 21% Carbon Dioxide - less than 1%
Which of the following statements correctly describes the relationship between atmospheric pressure and altitude?
Pressure decreases as altitude increases
According to Fick's law, what variables are important in the diffusion of a gas across cellular membranes?
The difference the gas' partial pressure on both sides of the membrane The thickness of the membrane
What limits the size of organisms that rely entirely on oxygen diffusion from the environment (and not on a transportation/exchange system of any kind)/?
The rate of oxygen diffusion
How do mammals achieve enormous surface areas in their lungs?
Their lungs are packed with millions of alveoli.
Which of the following is true about gas exchange in the anatomical dead space?
There is no gas exchange.
Which of the following statements about the membranes across which gas exchange in animals occurs is true?
They are always surrounded by water.
Which of the following are disadvantages of external gills?
They are easily damaged. They require large energy expenditure in order to be constantly moved.
How do invertebrates maximize diffusion?
They maximize the surface area for diffusion They decrease the distance over which gases travel They maximize delta-p in Fick's Law
What is the purpose of respiration?
To supply oxygen to body cells for synthesis of ATP and eliminate carbon dioxide that is produced by that reaction.
Gas exchange in all cells involves in the movement of gases
across cellular membrane
Gas exchange in all cells involves the movement of gases
across cellular membranes
Myoglobin oxygen reserves are used
after the hemoglobin oxygen reserve is exhausted
Multilobed air sacs that constitute the gas exchange surface in mammalian lungs are called ______.
alveoli
The lungs of mammals contain millions of tiny sacs clustered like grapes, though which gas exchange occurs. Theses tiny sacs are called
alveoli
The mammalian lung has enormous surface area because it is packed with millions of _______.
alveoli
The portion of the tidal volume that is contained in the tubular passages (trachea, bronchi, bronchioles) where no gas exchange occurs is called the _______ ________ space.
anatomical dead
The portion of the tidal volume that is contained in the tubular passages (trachea, bronchi, bronchioles) where no gas exchange occurs is called the ________ ________ space.
anatomical dead
In birds, air is forced in and out of the lungs with the help of
anterior and posterior air sacs
A condition characterized by smooth muscle contractions in bronchioles which can result in difficulty in breathing and wheezing is called _______.
asthma
Smooth muscle contractions in bronchioles which can result in difficulty in breathing and wheezing is a condition known as:
asthma
The formation of ______ ions in the red blood cells removes large amounts of CO2 from the plasma - in this way a _____ of CO2 is maintained allowing more and more CO2 to move into the blood from the surrounding tissues.
bicarbonate gradient
The formation of ______ ions in the red blood cells removes large amounts of CO2 from the plasma - in this way a ______ of CO2 is maintained allowing more and more CO2 to move into the blood from the surrounding tissues.
bicarbonate gradient
The formation of _______ ions in the red blood cells removes large amounts of CO2 from the plasma - in this way a ______ of CO2 is maintained allowing more and more CO2 to move into the blood from the surrounding tissues.
bicarbonate gradient
Signs of lung cancer include coughing and especially coughing up ______.
blood
Inhaled air moves down the trachea and into two branched tubes called the _____ that lead to each lung.
bronchi
The two tubes that branch from the trachea and lead to each lung are known as the
bronchi
Tubes in the lungs that branch from the bronchi and end in the alveoli are called ________.
bronchioles
Carbon dioxide lowers the pH of blood by combining with water to produce ______ acid which dissociates into a ______ ion and a proton.
carbonic bicarbonate
Carbon dioxide lowers the pH of blood by combining with water to produce ______ acid which dissociates into a _______ ion and a proton.
carbonic bicarbonate
The mantle cavity of mollusks
contains the gills opens to the outside
Neurons in the respiratory control center stimulate the diaphragm and external intercostal muscles to ______. When those neurons stop producing impulses, the inspiratory muscles ______ and air is exhaled.
contract relax
Neurons in the respiratory control center stimulate the diaphragm and external intercostal muscles to _______. When those neurons stop producing impulses, the inspiratory muscles ______ and air is exhaled.
contract relax
Neurons in the respiratory control center stimulate the diaphragm and external intercostal muscles to _______. When those neurons stop producing impulses, the inspiratory muscles _______ and air is exhaled.
contract relax
Typical symptoms of lung cancer tumors are
coughing coughing up blood
Due to the ______ flow of blood and water in the gills, _____ diffuses from water into blood along the entire length of the gills.
countercurrent oxygen
In bird lungs, the flow of blood and the flow of air are
crosscurrent
The process of exchanging gases across the skin is called _____ respiration.
cutaneous
The process of exchanging gases across the skin is called _______ respiration.
cutaneous
After the lungs are inflated with air, the external intercostal muscles and the _______ relax and recoil back to their original positions as an animal ______.
diaphragm exhales
Mammalian lungs are inflated when the ______ and the external ______ ______ simultaneously contract, increasing the chest cavity and thereby decreasing the gas pressure within them and allowing air to flow in.
diaphragm intercostal muscles
Gases move across cellular membranes by ______.
diffusion
In multicellular animals most of the cells are not in _____ contrast with the external environment, therefore those animals have to rely on specialized systems for transport and exchange of gases.
direct
In multicellular animals most of the cells are not in ______ contract with the external environment, therefore those animals have to rely on specialized systems for transport and exchange of gases.
direct
In multicellular animals most of the cells are not in _______ contract with the external environment, therefore those animals have to rely on specialized systems for transport and exchange of gases.
direct
A curve that shows the percent oxyhemoglobin saturation as a function of the oxygen partial pressure is known as a oxyhemoglobin _______ curve.
dissociation
Consider two breathing cycles in birds - cycle I is composed of inhalation I and exhalation I and cycle II follows immediately with inhalation II and exhalation II. Air taken in during inhalation I is returned to the atmosphere during _______ _______ (answer with inhalation/exhalation and I/II).
exhalation II
In addition to the diaphragm, the volume of the lungs in mammals is increased during inhalation with the help of the
external intercostal muscles
The pleural cavity is very small and filled with ______; this causes the two pleural membranes to adhere, effectively coupling the lungs to the _____ cavity.
fluid thoracic
The pleural cavity is very small and filled with ______; this causes the two pleural membranes to adhere, effectively coupling the lungs to the _______ cavity.
fluid thoracic
The maximum number of oxygen molecules that can bind to a single molecule of hemoglobin is ______.
four
The maximum number of oxygen molecules that can bind to a single molecule of hemoglobin is _______.
four
Diseases of the lungs usually lead to restricted ______ exchange.
gas
Oxygen is attached to the iron atom in the _____ of hemoglobin, while CO2 is attached to the _____ protein.
heme protein
Because in whole blood most of the oxygen is bound to the protein ______, more oxygen can be transported than in blood plasma.
hemoglobin
In contrast to hemoglobin, hemocyanin is usually found as a free protein in the _______ of arthropods and some mollusks.
hemolymph
Because it has ______ affinity for oxygen than hemoglobin, myoglobin provides oxygen in muscles after the oxygen reserves in hemoglobin have been depleted.
higher
Because it has ________ affinity for oxygen than hemoglobin, myoglobin provides oxygen in muscles after the oxygen reserves in hemoglobin have been depleted.
higher
The two-way flow of air during the ventilation of mammalian lungs is less efficient that the flow in birds, because
in two-way ventilation fresh and exhaled gases mix
As blood coming from the systemic circulation enters the lungs and moves through them, the partial pressure of oxygen in the blood
increases
When certain muscles in the body of mammals contract, the volume of the lungs ______. This creates ______ pressure relative to the outside air and draws air in to fill the lungs.
increases negative
When certain muscles in the body of mammals contract, the volume of the lungs ________. This creates _______ pressure relative to the outside air and draws air in to fill the lungs.
increases negative
In hemoglobin, oxygen binds to an atom of ______, while in hemocyanin, the oxygen-binding atom is ______.
iron cu
Within the ______ of the gills of fish are numerous capillaries, all oriented with blood flowing in the same direction, from the oxygen-poor vessel to the oxygen-rich one.
lamellae
Exhalation in mammals requires
less energy than inhalation.
A terrestrial organism with gills would
lose a significant amount of water through evaporation across the surface of gills
During hyperventilation, the partial pressure of carbon dioxide in blood becomes abnormally ____. During hypoventilation, the partial pressure of carbon dioxide in blood becomes abnormally ____.
low high
Breathing in a mammal will be strongly stimulated by a combination of ___ pH and ____ concentration of CO2 in the blood.
low high
The enzyme carbonic anhydrase catalyzes the conversion of H2CO3 into H20 and CO2 in the ________, and the conversion of H2O and CO2 into H2CO3 in _______.
lungs tissues
The enzyme carbonic anhydrase catalyzes the conversion of H2CO3 into H2O and CO2 in the _____, and the conversion of H2O and CO2 into H2CO3 in _____.
lungs tissues
Match the organisms to the level of mixing of fresh and oxygen-depleted air that occurs in their respiratory system.
mammals - fresh air is mixed with oxygen-depleted air birds - fresh air is never mixed with oxygen-depleted air
In living things, gas exchange always involves the movement of gases across a ______.
membrane
In living things, gas exchange always involves the movement of gases across a _______.
membrane
Oxygen is bound to which of the following components of respiratory pigments?
metal
Respiratory pigments are proteins containing one or more _____ atoms in their cores, to which oxygen binds.
metal
The traditional units used for measuring atmospheric pressure are
mmHg
In _____ pressure filling, lungs fill with air because the pressure in the lungs is lower than that of the atmosphere.
negative
During inhalation, neurons in the respiratory control center are producing impulses; during exhalation, neurons of the respiratory control center are
not producing impulses.
How many polypeptide chains does myoglobin have?
one
In birds, air flows in ______ direction(s) through the ______, while in mammals, air flows in ______ direction(s) through the alveoli.
one parabronchi two
In birds, air flows in ______ direction(s) through the _______, while in mammals, air flows in ______ direction(s) through the alveoli.
one parabronchi two
In birds, air flow in ______ direction(s) through the ______, while in mammals, air flows in ______ direction(s) through the alveoli.
one parabronchi two
In mammals, to oxygenate the blood in the lungs,
one cycle of inhalation and exhalation is(are) needed.
In contrast to mammals, air in birds flow in
one direction through the parabronchi
In hemoglobin
oxygen attaches to the Fe atom in the heme, while carbon dioxide attaches to the protein portion
Match different compartments in the mammalian body to the partial pressure of oxygen in them. All the given numbers are mm Hg.
oxygen depleted blood returning from systemic circulation - 40 alveoli - 105 fully oxygenated blood leaving the lungs - 100
Respiratory pigments such as hemoglobin facilitate transportation of
oxygen in the blood
The binding of oxygen to hemoglobin is influenced by other factors such as
pH temperature
In mammals, the thoracic cavity is lined with a thin membrane that aids in lung ventilation. This membrane is called the _______ ______ membrane.
parietal pleural
When each individual gas found in the air is considered separately, we can calculate the _____ pressure of that gas.
partial
The individual pressure of each gas found in air is known as its
partial pressure
The percent of hemoglobin molecules that are in the form of oxyhemoglobin is known as the
percent oxyhemoglobin saturation
Hemoglobin can bind oxygen and has a red color; therefore we refer to it as a respiratory _______.
pigment
The space enclosed between the visceral and parietal membranes (which line the lungs and the thoracic cavity, respectively) is called the _______ cavity.
pleural
In _____ pressure breathing, air is forced in the lungs, similar to filling a balloon with air.
positive
Although it is almost imperceptible, gases in the air exert ______ on surfaces, including the bodies of animals.
pressure
Although it is almost imperceptible, gases in the air exert _______ in surfaces, including the bodies of animals.
pressure
Respiratory flow that is created in some fish by opening the mouth during swimming, such that water flows through the mouth and across the gills is known as ______ ventilation.
ram
Respiratory flow that is created in some fish by opening the mouth during swimming, such that water flows through the mouth and across the gills is known as _______ ventilation.
ram
The production of respiratory flow in some fish in which the mouth is opened during swimming, such that water flows through the mouth and across the gills is called
ram ventilation
The most common effect of respiratory disease is
reduced gas exchange
The most common effect of respiratory disease of
reduced gas exchange
The oxygen-binding proteins that have evolved in animals are called _____ _____ because they have a color.
respiratory pigments
The oxygen-binding proteins that have evolved in animals are called ______ ______ because they have a color.
respiratory pigments
The oxygen-binding proteins that have evolved in animals are called ______ _______ because they have a color.
respiratory pigments
The percent of hemoglobin molecules in blood cells which are in the form of oxyhemoglobin constitute the percent oxyhemoglobin ________.
saturation
In mammals, ______ detect the pH and CO2 concentration of blood and interact with the ______ control center to regulate the rate and depth of ventilation by the lungs.
sensors respiratory
Blood pH and temperature can _____ the hemoglobin curve, optimizing the unloading of O2 in the tissues.
shift
Blood pH and temperature can _______ the hemoglobin dissociation curve, optimizing the unloading of O2 in the tissues.
shift
In cutaneous respiration, oxygen and carbon dioxide are exchanged across the ______.
skin
The bronchioles are
smaller tubes that branch from the bronchi and end in alveoli
Emphysema cases are usually the result of _______.
smoking
In order to meet the needs of a multicellular organism, its transport and exchange systems require very large _______ ______.
surface area
In order to meet the needs of a multicellular organism, its transport and exchange systems require very large _______ _______.
surface area
In order to meet the needs of every cell in a multicellular organism, transport and exchange systems are typically characterized by their very large
surface area
In fish, blood vessels run the length of filaments, with oxygen-poor blood traveling through
the incoming vessels along one side of the filament, and oxygen-rich blood returning through the outgoing vessel along the other side
When Fick's law is applied to gas diffusion through a membrane, Δp refers to
the pressure difference between the two sides of the membrane
In the lungs, the enzyme carbonic anhydrase catalyzes
the reaction H2CO3 -> H2O+CO2
The respiratory system that involves diffusion of oxygen and carbon dioxide directly into and out of cells at the fluid-filled tips of branching tubes is
the tracheal system of insects
In humans and other mammals, the outside of each lung is lined with
the visceral pleural membrane
The oxygen reserves in hemoglobin can be heavily used
to maintain life for 4-5 minutes if breathing or heart pumping are interrupted during exercise
In vertebrates, the cartilaginous tube that branches into the bronchi is the
trachea
Respiration in birds occurs is ______ cycle(s) - air inhaled during one cycle is exhaled during the ______ cycle.
two next
Respiration in birds occurs in _______ cycle(s) - air inhaled during one cycle is exhaled during the _______ cycle.
two next
Gas exchange membranes in animals are always surrounded by
water
Gas exchange membranes in animals are always surrounded by ________.
water
Lungs are better suited for gas exchange in air as they move air through branched tubular passages, thus minimizing the loss of _______.
water
