Globulins, albumins, and fibrinogen are the major blood proteins. The globulins are a family of globular proteins that have higher molecular weights than albumins and are insoluble in pure water but dissolve in dilute salt solutions. Fibrinogen comprises 7% of blood proteins; conversion of fibrinogen to insoluble fibrin is essential for blood clotting. All the blood proteins are synthesized in the liver except the gamma globulins.