Serum proteins are proteins found in blood plasma, which is the liquid component of blood. They play essential roles in various bodily functions, including maintaining osmotic pressure, transporting nutrients and hormones, and supporting the immune system. The main types of serum proteins include albumin, globulins, and fibrinogen. Albumin is the most abundant serum protein and helps regulate blood volume and pressure. Globulins are involved in immune responses and transport functions, while fibrinogen is crucial for blood clotting. The levels and types of serum proteins can provide important information about a person's health and are often measured in medical tests.