my talk is composed of three parts. the first part is on high order residual distribution (rd) schemes for steady state hyperbolic conservation laws. high order rd schemes are conservative schemes that overcome the restriction of mesh sizes in high order finite difference schemes, and yet have comparable computational costs. it has a broad range of applications from navier-stokes equations to semiconductor simulations. i will present the design of the scheme, a lax-wendroff type theorem and the numerical results. in the second part, i will discuss the applications in systems biology. the modeling of the two biological systems--cell polarization and multi-stage cell lineages, and the computational aspect will be discussed. new efficient numerical schemes for both time evolution and steady state reaction-diffusion equations that arise in many biological models will be presented in the third part.