Color Atlas of Anatomy A Photographic Study of the Human Body

Three general principles are recognizable in the architecture of the humanorganism:1. The principle of polarity: Polarity is reflected mainly in the formal andfunctional contrast between the head (predominantly spherical form) andthe extremities (radially arranged skeletal elements). In the phylogeneticdevelopment of the upright position of the human body, polarity developedalso among the extremities: The lower extremities provide the basis forlocomotion whereas the upper extremities are not needed anymore forlocomotion, so they can be used for gesture, manual and artistic activities.2. The principle of segmentation: This principle dominates in the trunk. Theanatomical structures (vertebrae, pairs of ribs, muscles, and nerves) are arrangedsegmentally and replicate rhythmically in a similar way.3. The principle of bilateral symmetry: Both sides of the body are separatedby a midsagittal plane and resemble each other like image and mirror-image