I think the different systems that we find of a building are very resembling to those in the human body because, ultimately, an effective, functioning system is one which is able to provide all the necessary things for optimal survival to everywhere it is needed, operating successfully and restored if something is broken. For instance, the nervous system in our bodies resembles the electrical system in our buildings, as electron particles flow through cables, providing us with the necessary stimuli to utilize out appliances, electronic equipments, and more. Similar to the brain, the electron flow is generated through electric grids. Additionally, essential nutrients for a building such as water, gas, and heat are also transported within a structure through complicated pipe systems, akin to our much-need circulatory system.