Gas Exchange
This process allows gases to move across respiratory surfaces
What is diffusion?
Respiratory surfaces must be this to allow gases to dissolve and diffuse.
What is moist?
Gas exchange in mammalian lungs occurs in these tiny air sacs.
What are alveoli?
Most oxygen in the blood is transported bound to this respiratory pigment.
What is hemoglobin?
The amount of air inhaled or exhaled during a normal breath.
What is tidal volume?
The pressure exerted by one particular gas within a mixture of gases.
What is partial pressure?
Name two characteristics that make a respiratory surface efficient.
What are large and thin?
Also acceptable: moist, folded, or branched.
Air travels from the trachea into these two major branches.
What are the bronchi?
Each hemoglobin molecule contains four of these iron-containing structures.
What are heme groups?
The amount of air that remains in the lungs after exhalation.
What is residual volume?
Oxygen moves from the alveoli into the blood because the partial pressure of O₂ is ______ in the alveoli than in the blood.
What is higher?
These respiratory structures allow aquatic animals to exchange gases with water.
What are gills?
Put these in the correct order: Alveoli → Trachea → Bronchioles → Bronchi
What is Trachea → Bronchi → Bronchioles → Alveoli?
One hemoglobin molecule can carry up to this many O₂ molecules.
What is four?
According to the slides, this gas is the main trigger for increasing breathing rate.
What is CO₂?
At sea level, the partial pressure of O₂ in inspired air is approximately this value.
What is 160 mmHg?
This highly efficient mechanism allows fish to extract oxygen from water by maintaining a gradient along the gill.
What is countercurrent exchange?
During inhalation, the diaphragm does this while the rib cage expands.
What is contracts and flattens?
Hemoglobin exhibits this property: when one subunit binds O₂, the other subunits become more likely to bind O₂.
What is cooperative binding?
The brain region that receives information about CO₂ and helps regulate breathing.
What is the medulla?
n body tissues, PO₂ is generally ______ 40 mmHg while PCO₂ is generally ______ 45 mmHg.
What are less than; greater than?
Unlike mammals, insects can transport O₂ and CO₂ directly through a network of air tubes without relying on the circulatory system.
What is the tracheal system?
This substance coats the alveoli and helps prevent the problems associated with alveolar collapse; premature babies may lack enough of it.
What is surfactant?
During exercise, increased CO₂ and acidity cause hemoglobin to release more O₂ to active tissues. This phenomenon is called this.
What is the Bohr shift?
During inspiration, the diaphragm contracts and the thoracic cavity expands. What happens to pressure inside the lungs, and why does air enter?
What is lung pressure decreases, causing air to flow into the lungs?