The major function of the respiratory system is to proivide the blood with oxygen to fuel it to deliver oxygen into the oter parts of the body. The respiratory is responible for the distribution of the needed oxygen supply to keep the brain from functioning. This happens due to respiration, or the process of breathing in, and out.
We inhale oxygen when we breathe, and the body distributes this oxygen through the bloodstream which then will be supplied throughout. In turn, the body provides the blood with carbon dioxide, a waste gas, and then exhaled out of the body.