(1) Plasma proteins are large molecules with molecular weights ranging mostly from 50,000 to 300,000 Daltons.

(2) With the notable exception of albumin, nearly all plasma proteins are Glycoproteins, containing oligosaccharides. The oligosaccharide chains are responsible for certain properties of plasma proteins like solubility, viscosity, charge, denaturation etc.

(3) like most other proteins, their charged residues tend to be located on the surface.

(4) Many plasma proteins exhibit polymorphism. Polymorphism is a Mendelian trait that exists in the population in at least two phenotypes, neither of which is rare. Plasma proteins showing polymorphism are haptoglobin, transferring, ceruloplasmin, and immunoglobulin. Due to the large size of the protein molecules,

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(5) they can be separated from the plasma by ultracentrifugation (unlike electrolytes or other smaller molecules).

(6) They are unable to pass across the capillary membrane and consequently exert an oncotic pressure of about 25 mm Hg.

(7) Owing to their size and particularly their shape, they greatly contribute to blood viscosity. The plasma protein fibrinogen is a significant contributor to blood viscosity. Due to the presence of polar residues on their surfaces,

(8) the protein molecules are soluble in water.

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(9) The molecules show electrophoretic mobility.

(10) The molecules are amphoteric. This is because the polar residues comprise both NH2 and COOH groups.

(11) They act as efficient buffers by virtue of their amphoteric nature.

(12) They easily bind with metallic ions and steroids. The bonds are formed with the polar residues.