The sequence-structure-function relationship for proteins is well established, but are there corresponding relationships at larger scales, from organelles to specialized subcellular structures? My research seeks to address how molecular organization influences the shape of cellular membranes. In this talk I will discuss our recent progress towards developing approaches to enable the incorporation of biological complexity in models of cellular membrane mechanics. This includes a new simulation engine called Mem3DG which uses concepts from discrete differential geometry to model the coupled mechochemical feedback of in-plane membrane components interacting with membrane geometry. I will show biological problems we have been able to address and give a perspective on possible directions for future mathematical and computational development.