The blood plasma is filtered through the capillaries of the glomerulus of the kidney. The glomerulus, more specifically the Bowman's Capsule, empties the filtrate and anything that isn't filtered will pass into the proximal convoluted tubule where reabsorption of nutrients, and water take place.
As the blood requires more nutrients, active transport is required to reabsorb the nutrients from the proximal tubule, while passive transport is used via osmosis to reabsorb water back into the blood.
