An increase in the partial pressure of oxygen causes pulmonary arterioles to ________, thereby altering ________ to make gas exchange more efficient. constrict; ventilation dilate; ventilation constrict; perfusion dilate; perfusion
when blood pressure increase the arterioles dilate (become smaller) so that cells can absorb the oxygen from the blood easily. perfusion will be altered or slowed down. (The perfusion is the passage of fluid through the circulatory system. )
