Membrane structures are thin layers that separate different environments or compartments. They are essential in biological systems, forming the boundaries of cells and organelles. These membranes are primarily composed of phospholipids, proteins, and carbohydrates, which help regulate the movement of substances in and out of cells. In addition to biological membranes, membrane structures can also refer to synthetic materials used in construction and engineering. These structures are often lightweight and flexible, making them suitable for various applications, such as roofing and tents. They provide protection from environmental elements while maintaining structural integrity.