When you inhale oxygen comes in then goes though trachea then lungs and into aveoli Then the blood carry oxygen to our body cells to remove carbon dioxide
A,C, D.. Those are correct ..
Biology is the study of living organisms, divided into many specialized fields that cover their morphology, physiology, anatomy, behavior, origin, and distribution.
This is basically the definition of biology, so you may need to add a little more detail. This is a great way to get it started though!!!
Hope this helps!!
