1
Respiratory
Airway and lungs
2
Circulatory
Heart, blood, and blood vessels
3
Nervous
Brain, spinal cord, and nerves
4
Musculoskeletal
Bones, ligaments, muscles, and tendons
5
Integumentary
Skin, hair, and nails
6
Endocrine
Glands
7
Digestive
Mouth, esophagus, stomach, and intestines
8
Genitourinary
Kidneys, bladder, Uterus, genitalia