Most mornings, Randy listens to his favorite song as he gets ready for work, including putting in his contacts. One afternoon, Randy hears his favorite song playing, and his eyes start watering... something that usually happens only when he puts his contacts in. This is an example of
classical conditioning. What is the unconditioned stimulus?
a. eye watering
b. the contacts
c. the song
d. getting ready for work

What is the difference between the conducting zone and the respiratory zone of the respiratory system? the conducting zone is a series of cavities and tubes that move air to the respiratory zone where gases exchange with the bloodstream. the conducting zone exchanges gases between the lungs and the alveoli and the respiratory zone is a series of cavities and tubes that move air to the conducting zone. the conducting zone moves oxygen into the cells and the respiratory zone takes carbon dioxide away from the cells. the conducting zone moves oxygen into the bloodstream and the respiratory zone takes carbon dioxide away from the bloodstream.