BIO1108 TEST 2 STUDY GUIDE
QUESTIONS WITH CORRECT
ANSWERS
What does it mean to ventilate? - Answer- To move the air/water across the respiratory
surface.
What does it mean to perfuse? - Answer- To circulate.
What process is the only means of gas exchange across these surfaces? - Answer-
Diffusion.
What physical factors can influence rates of diffusion? - Answer- Size and Temperature.
What does diffusion result in? - Answer- The net movement of molecules from areas of
higher concentration to areas of lower concentration.
Where does the diffusion of respiratory gases occur? - Answer- In water or air.
What is air? - Answer- Mixture of gases. More specifically, Nitrogen (N2;78.6%),
Oxygen (O2; 20.9%),Water Vapor (H2O; 0.5%), and Carbon Dioxide (CO2; 0.04%).
What is the concentration of gas expressed as? - Answer- Partial pressure.
What is total atmospheric pressure? - Answer- Pressure exerted by all gases in the air.
What is total atmospheric pressure at sea level? - Answer- 760 mm Hg.
T/F: Atmospheric pressure is lower at higher elevations. - Answer- True.
We can calculate the partial pressure of O2 at sea level? - Answer- By multiplying the
percent of O2 (converted to a decimal) by the total atmospheric pressure at sea level
(760 mm Hg.).
Aquatic invertebrates without internal systems for gas exchange are mostly
__________________ in size. - Answer- Small.
quatic invertebrates without internal systems for gas exchange have _____________
bodies to increase ___________________________. - Answer- Flat; Surface Area.
,What type of animals have specialized gas exchange surfaces (gills)? - Answer- Large.
What are some adaptations to maximize respiratory gas exchange? - Answer- Increase
SA, Maximize partial pressure gradients, minimize diffusion path length, and minimize
diffusion that takes place in an aqueous medium.
What are the function of external gills? - Answer- To minimize the diffusion path length
in water.
What is a disadvantage of external gills? - Answer- They are not protected from
predators and damage.
What is an advantage of internal gills? - Answer- They are protected from predators and
damage.
What are lungs? - Answer- Internal cavities for respiratory gas exchange with air.
What are tracheae? - Answer- Air-filled tubes in insects.
What kind of respiratory system do insects have? - Answer- Tracheal Respiratory
System.
Where are spiracles located and what do they do? - Answer- The abdomen; They open
to allow gas exchange; close to limit water loss.
Where do the spiracles lead to? - Answer- Into tubes called tracheae, which branch to
tracheoles, and end in air capillaries, which are the gas exchange surfaces.
Bird lungs have little ________________ _______________? - Answer- Dead space.
In birds, what structure receives inhaled air, but is not the site of gas exchange? -
Answer- Air sacs.
What is the flow of air in the birds respiratory system? - Answer- Air enters through the
trachea, which divides into primarybronchi, which extend to the posterior air sacs and
branch into secondary bronchi. The secondary bronchi branch into parabronchi, which
run parallel to one another through the lungs. Parabronchi coalesce into larger bronchi
that bring air to the anterior air sacs and back to the trachea
What is tidal respiration? - Answer- When air flows in and out of lungs by the same
path.
What is Tidal Volume (TV)? - Answer- The amount of air that moves in and out per
breath when at rest.
, How does air initially enter the human lungs? - Answer- Through the mouth or nasal
passage.
Where does the mouth and nasal passage join? - Answer- The pharynx.
What structure is below the pharynx? - Answer- The trachea.
What structure is at the beginning of the airway?
Hint: Also known as the voice box. - Answer- The larynx.
What does the trachea branch into? - Answer- Two bronchi.
What do bronchi branch into? - Answer- Bronchioles.
where do bronchioles end? - Answer- Alveoli.
Where are the sites of gas exchange in the human body? - Answer- The Alveoli.
Alveoli have thin walls and are surrounded by what? - Answer- Capillaries.
What is emphysema? - Answer- A condition in which the alveoli walls are damaged and
inflamed, causing breathlessness.
What do mammalian lungs secrete that affect ventilation? - Answer- Mucus and
Surfactant.
What is secreted by cells lining airways and captures dirt and microorganisms? -
Answer- Mucus
What is the mucus escalator? - Answer- When cilia sweeps the mucus and trapped
particles out of the airways.
What does surfactant do? - Answer- Reduces the surface tension of a liquid.
What does surface tension result from? - Answer- The attraction between water
molecules.
What is surfactant and what does it do? - Answer- Surfactant: surface active substance
which coats the alveoli and reduces surface tension.
Lung surfactant is released by cells in the alveoli when they are _____________. -
Answer- Stretched.
Why is surfactant important? - Answer- It is critical for reducing the work needed to
inflate the lungs.
QUESTIONS WITH CORRECT
ANSWERS
What does it mean to ventilate? - Answer- To move the air/water across the respiratory
surface.
What does it mean to perfuse? - Answer- To circulate.
What process is the only means of gas exchange across these surfaces? - Answer-
Diffusion.
What physical factors can influence rates of diffusion? - Answer- Size and Temperature.
What does diffusion result in? - Answer- The net movement of molecules from areas of
higher concentration to areas of lower concentration.
Where does the diffusion of respiratory gases occur? - Answer- In water or air.
What is air? - Answer- Mixture of gases. More specifically, Nitrogen (N2;78.6%),
Oxygen (O2; 20.9%),Water Vapor (H2O; 0.5%), and Carbon Dioxide (CO2; 0.04%).
What is the concentration of gas expressed as? - Answer- Partial pressure.
What is total atmospheric pressure? - Answer- Pressure exerted by all gases in the air.
What is total atmospheric pressure at sea level? - Answer- 760 mm Hg.
T/F: Atmospheric pressure is lower at higher elevations. - Answer- True.
We can calculate the partial pressure of O2 at sea level? - Answer- By multiplying the
percent of O2 (converted to a decimal) by the total atmospheric pressure at sea level
(760 mm Hg.).
Aquatic invertebrates without internal systems for gas exchange are mostly
__________________ in size. - Answer- Small.
quatic invertebrates without internal systems for gas exchange have _____________
bodies to increase ___________________________. - Answer- Flat; Surface Area.
,What type of animals have specialized gas exchange surfaces (gills)? - Answer- Large.
What are some adaptations to maximize respiratory gas exchange? - Answer- Increase
SA, Maximize partial pressure gradients, minimize diffusion path length, and minimize
diffusion that takes place in an aqueous medium.
What are the function of external gills? - Answer- To minimize the diffusion path length
in water.
What is a disadvantage of external gills? - Answer- They are not protected from
predators and damage.
What is an advantage of internal gills? - Answer- They are protected from predators and
damage.
What are lungs? - Answer- Internal cavities for respiratory gas exchange with air.
What are tracheae? - Answer- Air-filled tubes in insects.
What kind of respiratory system do insects have? - Answer- Tracheal Respiratory
System.
Where are spiracles located and what do they do? - Answer- The abdomen; They open
to allow gas exchange; close to limit water loss.
Where do the spiracles lead to? - Answer- Into tubes called tracheae, which branch to
tracheoles, and end in air capillaries, which are the gas exchange surfaces.
Bird lungs have little ________________ _______________? - Answer- Dead space.
In birds, what structure receives inhaled air, but is not the site of gas exchange? -
Answer- Air sacs.
What is the flow of air in the birds respiratory system? - Answer- Air enters through the
trachea, which divides into primarybronchi, which extend to the posterior air sacs and
branch into secondary bronchi. The secondary bronchi branch into parabronchi, which
run parallel to one another through the lungs. Parabronchi coalesce into larger bronchi
that bring air to the anterior air sacs and back to the trachea
What is tidal respiration? - Answer- When air flows in and out of lungs by the same
path.
What is Tidal Volume (TV)? - Answer- The amount of air that moves in and out per
breath when at rest.
, How does air initially enter the human lungs? - Answer- Through the mouth or nasal
passage.
Where does the mouth and nasal passage join? - Answer- The pharynx.
What structure is below the pharynx? - Answer- The trachea.
What structure is at the beginning of the airway?
Hint: Also known as the voice box. - Answer- The larynx.
What does the trachea branch into? - Answer- Two bronchi.
What do bronchi branch into? - Answer- Bronchioles.
where do bronchioles end? - Answer- Alveoli.
Where are the sites of gas exchange in the human body? - Answer- The Alveoli.
Alveoli have thin walls and are surrounded by what? - Answer- Capillaries.
What is emphysema? - Answer- A condition in which the alveoli walls are damaged and
inflamed, causing breathlessness.
What do mammalian lungs secrete that affect ventilation? - Answer- Mucus and
Surfactant.
What is secreted by cells lining airways and captures dirt and microorganisms? -
Answer- Mucus
What is the mucus escalator? - Answer- When cilia sweeps the mucus and trapped
particles out of the airways.
What does surfactant do? - Answer- Reduces the surface tension of a liquid.
What does surface tension result from? - Answer- The attraction between water
molecules.
What is surfactant and what does it do? - Answer- Surfactant: surface active substance
which coats the alveoli and reduces surface tension.
Lung surfactant is released by cells in the alveoli when they are _____________. -
Answer- Stretched.
Why is surfactant important? - Answer- It is critical for reducing the work needed to
inflate the lungs.
