Final answer:
The plasma membrane is described by the fluid mosaic model as being composed of a bilayer of phospholipids and proteins that give it fluid character, enabling movement within the membrane while maintaining cell integrity.
Step-by-step explanation:
A plasma membrane is covered by a continuous plasma membrane that consists of a mosaic of different types of localized domains. The structure and functions of the plasma membrane are described by the fluid mosaic model, which explains that the membrane's construction is a bilayer composed mainly of phospholipids and proteins. These components, including phospholipids, cholesterol, proteins, and glycolipids, grant the membrane its fluid character, allowing for lateral movement within the plane of the membrane while maintaining its integrity.
The plasma membrane is a critical barrier of the cell, separating internal contents from the external environment. Integral proteins span the bilayer, anchored in place by hydrophobic interactions, while peripheral proteins attach to the membrane's surface. The combination of flexibility and the presence of various proteins and lipids create a functional barrier for the cell.