Oxygen passes from the outside air, ?

Question

into the Respiratory system and then on to the Circulatory system. What structures will a molecule of Oxygen pass through on its way from a point six inches in front of your face, to the Aorta?

I just don't understand this question can anyone help

Answer 1

Nose (or mouth) > trachea > lungs > bloodstream (capillaries) > arteries

Look at a diagram of the respiratory system to follow its path.

Added Later:

Oops, not certain if O2 passes through the heart before reaching the aorta.  Also there are more (minor?) structures involved.

Suggest you go to http://en.wikipedia.org, plug Respiratory system into search box, for complete reading...depends on how thorough a path your instructor wants.

Answer 2

for example when we keep a glass with full of cold water there will be water droplets outside the air this proves oxgen in the air