Definition
A semipermeable membrane allows some substances to pass through but not others. It's like a selective gatekeeper, letting some things in while keeping others out. Think of a cell membrane, which allows water to enter but blocks larger molecules. Unlike permeable materials that allow everything through, semipermeable materials are more restrictive. They are essential in biological systems for maintaining balance and regulating transport. It's a critical concept in biology, chemistry, and even some industrial processes. In essence, it's selectively permeable.