Figure 3.

Effects of neglecting features i–iv in modified Krogh models. Shown is PO₂ at tissue edge (r=R_t) vs. axial location (z) for full model that includes Michaelis-Menten consumption, intravascular resistance, Mb facilitation, and axial diffusion in the tissue; and models that neglect one of these. A: Model without IVR has tissue PO₂ about 25mmHg higher than full model, while model without Mb has slightly lower PO₂ in lethal corner. B: Model with constant consumption has lower PO₂ at all locations and gives zero PO₂ for last 50µm, while model with no axial diffusion has higher PO₂ at arterial end and lower PO₂ at venous end.