Predict how a cell would be affected if the cell membrane did not have any cholesterol molecules?

Because of the way cholesterol is shaped, part of the
steroid ring (the four hydrocarbon rings in between the hydroxyl group and the
hydrocarbon "tail") is closely attracted to part of the fatty acid chain on the nearest
phospholipid. This helps slightly immobilize the outer surface of the membrane and make
it less soluble to very small water-soluble molecules that could otherwise pass through
more easily.

Without cholesterol, cell membranes would be
too fluid, not firm enough, and too permeable to some molecules. In other words, it
keeps the membrane from turning to mush.

While cholesterol
adds firmness and integrity to the plasma membrane and prevents it from becoming overly
fluid, it also helps maintain its fluidity.

At the high
concentrations it is found in our cell’s plasma membranes (close to 50 percent, molecule
for molecule) cholesterol helps separate the phospholipids so that the fatty acid chains
will not come together and cyrstallize.

Therefore,
cholesterol helps prevent extremes-- whether too fluid, or too firm-- maintaining the
integrity and consistent fluidity of the cell surface membrane.