In space, astronauts use specially designed toilets that function in microgravity. These toilets use air flow and a vacuum system to handle waste. For urination, a funnel and hose system helps direct urine into a collection tank, which can be recycled into drinking water. For defecation, astronauts use a seat with thigh straps to keep them in place, and waste is collected in a bag or container. The system is engineered to handle the challenges of zero gravity and ensure hygiene and comfort during space missions.