Energy produced by the various process of respiration stored in the form of ATP within the tissues
Arctic <u>cod</u> , fish that produces antifreeze proteins in its blood.
If the inner lining of the air sacs neither thin nor highly vascularized, then it can be inferred that AIR SACS ARE CANNOT BE THE SITES OF GASEOUS EXCHANGE BETWEEN AIR AND BLOOD. Air sacs are generally lined with mucus and surrounded with blood capillaries.
In case of birds, air sacs play an important role in respiratory system.
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