osmosis
osmosis is the diffusion of water (from higher to lower concentration) through the cell's plasma membrane. this process is necessary for the african bush viper because osmosis allows the african bush viper to receive nutrients and dispose waste from the cell. osmosis also creates a stable environment for the cells, equalizing the outer and inner parts of the cell so the membrane would not cave in. another reason osmosis necessary is because it purifies the bloodstream, having toxic wastes in the loos can kill the viper.
diffusion
diffusion is the movement of molecules from higher concentration, to lower concentration across the plasma membrane. diffusion is significant because it allows the transfer (transport) of nutrients/molecules, like food. it also releases waste for the cell...diffusion does all of this for the cell, and no energy is even needed which is great for the cell!