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.
Symbiosis is the ecological relationship between two or more organisms living closely together with some form of feeding relationship involved. The three main symbiotic relationships are: - Mutualism, where both organisms benefit. - Commensalism, where one organism benefits while the other organism is not harmed. All of them thrive off of the other organism.
Answer:
The more derived characteristics organisms share,the greater their degree a kinship. For instance,a derived characteristic in plants is the presence of the vascular tissue.Although all organisms share similar traits.
Explanation:
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