Michael Elsohn Ross 
Body Cycles [PDF ebook] 

The body repairs and renews itself again and again – in cycles. BODY CYCLES describes and illustrates three of them. First is the cycle by which the body continually repairs itself, for examples by regrowing hair and nails. Next is the breath cycle, in which the lungs will with oxygen and release carbon dioxide over and over again. And third is the blood cycle, in which the circulatory system delivers oxygen and nutrients to all parts of the body.