What are the colloid osmotic pressures on the two sides of the glomerular filtration membrane?

1. Colloid osmotic pressure comes from proteins that cannot cross the barrier. 2. Red and white cells, platelets, albumins and other large proteins stay inside the capillary. 3. Those retained proteins create an average colloid osmotic pressure of 30 mm Hg within the capillary. 4. Almost no protein reaches the capsular lumen, so the osmotic pressure there is near zero. 5. The imbalance means the colloid term acts as a pure inward pull that opposes filtration. 6. Putting the 30 mm Hg on the capsular side would reverse that pull and predict filtration where none occurs. 7. Making the two sides equal would cancel the colloid term entirely and inflate the calculated net pressure. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 25 "The Urinary System", section 25.5 Physiology of Urine Formation_