Statement - I : If blood cells are placed in pure water, they swell and burst
Statement - II : Due to osmosis, the movement of water molecules into the cell dilutes the salt content.

(I) is True

Pure water(Lower concentration region), Fluids in Blood cell(High concentration region)

Due to Osmosis water flows from pure water to Blood cells. Thus blood cells swell & burst

This is called Haemolysis

(II) is true

Fluids in Blood  are less concentrated than salt sol.

Due to which water flows from Blood cells to salt sol.

Due to which not only salt sol. gets diluted but blood cells shrink.

This is called plasmolysis.