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.
The correct formulae is CCl4
Answer:
clean
Explanation:
privacy comfortable easy to use
The answer is B because the humoral immune response is mediated by antibody