Crenation is likely to occur in blood cells immersed in

Crenation is likely to occur in blood cells immersed in a solution of low water potential ( hypertonic solution) . The cytoplasm has higher water potential than outside solution, water leaves by osmosis. The cell shrinks and little spikes appear on the cell surface membrane. This process is called crenation. An animal cell will become dehydrated and eventually die when placed in a cell of lower water potential.

Its sugar, it can vary from nucleotide to nucleotide.