Some aspects of buildings that draw comparison to biological systems include:
Building exterior - Analagous to skin/fur. Provides passive temperature regulation, security, and some structural support. Also gives a huge aesthetic impression; similar to how humans use skincare and makeup, different exterior finishes and materials determine the visual vibes that a building projects
Structural system - Analagous to skeletal system; provides main structural support and framework on which the rest of the body lies
HVAC system - Analagous to circulatory/respiratory systems. HVAC systems regulate termpeature, humidity, and air quality. Similarly, blood circulation affects body temperature (circulatory) and things like nose hair/lung mucus provide physical filtration of harmful substances from the air we breathe (respiratory)