Physical Human

Starting with key of C (left, above horizon) moving clockwise: C-DNA, genetic code, Db- Muscular system, D-Respiratory system, Eb-Lymphatic-Immune system, E-circulatory system, F-Digestive system, F#-Autonomic nervous system, G-Reproductive system, Ab-Central nervous system, A-Skeletal system, Bb-Integumentary system, B-Hormonal system