It expels gas to descend, and expels water from trim bladders to rise.

它通过排出气体来下降，并通过把水排出气囊来上升。

Why does bladderwrack have bladders?

泡叶藻为什么长着气泡？

Do Na 'vi actually have gall bladders?

Navi族真的有胆囊吗？

To eat their gall bladders and buried victims in ditches.

吃掉胆囊，受害者的尸首就被丢在沟壑中。

Piranhas produce noises by vibrating, or moving their swim bladders.

食人鱼通过震动或者移动它们的鱼鳔来制造声音。