#respiration notes

-- delivery of oxygen to blood

-- ventilation is required

-- oxygenation is required for respiration

-- oxygenation does not ensure respiration

-- ventilation does not ensure oxygenation

-- surrounding air contains about 21% oxygen

-- exhaled air contains about 16% oxygen

-- back-up system to the carbon dioxide drive

-- there are specialized sensors that monitor oxygen levels

-- these sensors are in the brain, the aorta, and the carotid arteries

-- low oxygen levels stimulate breathing

-- less effective than the carbon dioxide drive