They had to change they way they live which is quite difficult it is like you going to a new school in a new state and not being used to anyone
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.
Answer:
living organisms are composed of cells.
Organelles cannot survive alone
cells multiply through division
Explanation:
