Plasma proteins form about 7% of the blood plasma. They are the second largest constituents of plasma. Different plasma proteins include albumin, globulin, heparin, fibrinogen, prothrombin etc.
Functions:
(1) Albumin – (4%) It is the smallest plasma protein. It is synthesized in liver. It provides colloidal osmotic pressure to the plasma. It helps in transportation of important substances in blood. It is also an important buffering agent of blood.
(2) Globulin – (2.5%) It is mainly formed in lymphoid organs. They are the protein antibody which provides immunity to the body. Also they help in transportation of important substances in blood.
(3) Fibrinogen – (0.3%) It is synthesized in liver. It helps in blood clotting.
(4) Prothrombin – (0.03%) It is also synthesized in liver and is the second factor for blood clotting.
(5) Heparin – It acts as an anticoagulant.
