Answer:
The cilia is one of the things that act defensively in the respiratory system.
Explanation:
It propels a mucus-like liquid that covers the airway which traps pathogens (potentially infectious microorganisms) and other particles, preventing them from reaching the lungs.
B is correct, Organisms in the same group have similar characteristics
The answer is c. Hope this helps
Answer:
C. Systemic arterioles respond to a decrease in PO₂ by dilating, but pulmonary arterioles constrict in response to decreased PO₂.
Explanation:
In the arterioles, vasoconstriction is a response to high oxygen while vasodilation is a response to carbon dioxide and low pH. However, in the pulmonary arterioles, vasoconstriction occurs as a response to low oxygen and this mechanism is called hypoxic pulmonary vasoconstriction (HPV).
