In building systems, we can find similarities to biological systems, it feels almost easy to compare the two. In early architecture, the human body was seen as an inspiration to design, so many systems were modeled after this thought process. Much of how architecture came to form by being modeled after biological systems. Building systems came from this, and in many cases can be directly correlated to biological systems.
This can be seen first in circulation systems and diagrams of buildings. Similar to circulatory systems of bodies, building circulation runs through and connects all of a building's elements.
Another similarity in building and biological systems comes in the protection of vital organs. In the human body, vital organs are protected by bones, muscle, fats, and really anything possible to keep the body running. In a building system, the systems and structure that keep thee building standing and running are hidden from the naked eye in most cases, protecting these systems behind walls, under floors, above ceilings, etc.