Plasma oncotic pressure (colloid osmotic pressure) is primarily maintained by:

• A Sodium chloride
• B Gamma globulins
• C Albumin ✓
• D Fibrinogen

Explanation

Plasma oncotic pressure (approximately 28 mmHg total) is generated mainly by albumin, which accounts for roughly 70-80% of the total colloid osmotic pressure due to its high concentration (~4 g/dL) and relatively low molecular weight (66 kDa). Albumin also carries a slight negative charge that attracts additional cations (Gibbs-Donnan effect), adding approximately 3-4 mmHg. Hypoalbuminemia (nephrotic syndrome, cirrhosis, malnutrition) reduces oncotic pressure and causes edema.

Reference: Guyton & Hall, Textbook of Medical Physiology, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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