Examples of air sac

• No trematodes were observed in the lung or air sac, heart, liver, spleen and kidney of all bats and swallows.

• Tested organs include lung or air sac, heart, spleen, liver, kidneys and intestine.

• Alterations consisted of thickened air sac walls (fig. 1e), lesions or granulomata at the site of worm attachment, sometimes involving underlying tissues.

• The lung or air sac, heart, liver, spleen, kidney and intestine were collected using different sets of instruments in order to prevent possible cross-contamination.

• Some experiments involve the introduction of tobacco smoke into the animal's mouth or, in the case of hens, into the air sac.

• It was probably hollowed out by an outgrowth of an air sac in the nasal bone.

• This air sac leaves distinctive marks or opening on the bones, including a distinct opening in the upper arm bone ("humerus").

• Air from the lungs is channeled to the air sac, which resonates to make the sound louder.