Figure 5. Multiscale biomechanical response of murine skin as compared to model tissue.

Nominal stress (black) and Orientation Index (blue) variations as a function of the global stretch applied to skin sample from the same K14-COL5A1 mouse as in Figs 2 and 3 (a) and to a model connective tissue (b). Both nominal stress and OI exhibit a linear dependence with strain in the same region. Four parameters characterize the mechanical response, as seen in (b), the tangent modulus (1), the heel region length (2), the failure stretch ratio (3) and the ultimate tensile strength (4). The OI behavior in (b) is extrapolated from the classical interpretation of the microstructural origin of the stress/stretch curve.