Read the following statements about the urine formation and mark the incorrect statement.

The osmolarity gradually increases from inner medulla to outer medulla

to produce hypertonic urine

The collecting duct allows passage of small amounts of urea into the medullary interstitium

On an average, 1100-1200 ml of blood is filtered by kidneys per minute

70-80 per cent of electrolytes and water are reabsorbed by PCT