Is a straw-coloured fluid in the blood which contains 90% water. Plasma also contains the following:
• Proteins such as fibrinogen (aids blood clotting ), serum albumin (absorbs materials in the blood) and serum globulin (antibodies)
• Prothrombin which is an enzyme which aids blood clotting
• Inorganic materials such as chlorides and phosphates
• Digested food in the form of glucose and amino acids
• Nitrogenous wastes as a result of metabolism in the tissues.