In the Respiratory Cycle of Birds, Air Flows Through the Trachea

question 43

Multiple Choice

In the respiratory cycle of birds, air flows through the trachea, to the bronchi, and then

• A) into the parabronchi.
• B) back through the trachea.
• C) to the air capillaries.
• D) into the posterior air sacs.
• E) into the anterior air sacs.

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Definitions:

Dynein

A motor protein in cells which uses the energy from ATP to transport cellular cargo along microtubules towards the cell's nucleus.

Microtubules

Hollow, cylindrical fibers consisting of tubulin protein subunits; major components of the cytoskeleton and found in mitotic spindles, cilia, flagella, centrioles, and basal bodies.

ATP

Adenosine triphosphate, an organic compound that provides energy to drive many processes in living cells.

Eukaryotic Flagellum

Eukaryotic Flagellum refers to a lash-like appendage that protrudes from the cell body of certain eukaryotic cells, used primarily for locomotion.