Design a closed‑loop, biologically integrated life‑support system for a 4‑person Mars habitat that recycles air, water, and nutrients using microbial bioreactors and plant growth modules. Assessment covers: selecting appropriate microbial and plant processes; sizing reactors and growth areas with mass, nutrient, and energy balances; integrating water purification and nutrient recovery; meeting atmospheric (O2/CO2), potable water, and food targets; and meeting specified energy and redundancy constraints. Submit a schematic, key calculations (budgets and throughput), component specifications, failure‑mode/redundancy plan, and a concise engineering justification grounded in biological and systems principles.