Involuntary weight loss exceeding 10 pounds or 5% of body weight over a period of a few months is cause for concern. Tests are done based on the person's symptoms and findings on physical examination.
Fluid Mosaic Model. A model of membrane structure; according to this model, membranes are composed of a double layer of phospholipids in which various proteins are embedded. The phospholipid bilayer is a somewhat fluid matrix that allows the movement of proteins within it.hospholipid Bilayer. A double layer of phospholipids that forms the basis of all cellular membranes. The phospholipids heads, which are hydrophilic, face the water of extracellular fluid or the cytoplasm; the tails, which are hydrophobic, are buried in the middle of the bilayer.
Remember these key points: 1  Cell membranes or plasma membranes consist of a phospholipid bilayer with proteins embedded in the membrane. 2  Most of the functions of plasma membranes are handled by the proteins. 3  This arrangement of proteins and phospholipids is often called the fluid mosaic model for a cell membrane.he Actual Cell membrane has proteins embedded in the lipid bilayer. Embedded in the phospholipid bi-layer are a diverse set of proteins which do most of the important functions of the cell membrane. This idea is called the fluid mosaic model of the cell membrane.