Quantifying the characteristics of biological membranes is challenging. The multiscale nature of biological phenomena, complex structure, and non-equilibrium properties are some of the main difficulties. The focus of this project is to develop cellular and subcellular scale models of biological membranes.  At the cellular scale, fluid-structure interaction (FSI) methods are used to study red blood cells (RBCs) deformation in fluid flow. The FSI model involves a Lattice-Boltzmann fluid solver coupled with the spring-connected RBC model by the immersed-boundary method. We aim to establish a multiscale predictive model that is able to quantify blood cell damage in biomedical devices. Since the pore formation is a nanoscale phenomenon, a subcellular, particle-based, coarse-grained model is developed for the membrane of red blood cells that includes the RBC cytoskeleton. I employed non-equilibrium molecular dynamics to study pore formation, growth, and recovery of transient pores.