If you're a fat molecule forming the inner layer of a cell membrane, your head will face toward

Ok, thanks.

Huh?

Ya mean is it hydrophobic or not? I can't remember.



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The watery environment outside the cell

The most important lipids (or fats) in a cell membrane are phospholipids. Phospholipids have a hydrophilic (water-loving) head and a hydrophobic (water-fearing) tail. In water, phospholipids can organize into sheets that are two layers thick. The oily tails of the lipids point inward toward one another, while the hydrophilic heads point outward.

The diagram at Wikipedia shows the hydrophilic heads pointing outward into the aqueous environment, both inside the cell and outside. The space between the two layers is hydrophobic and so makes a good boundary between the inside of the cell and the outside of the cell.

Lipid bilayer - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Lipid_bilayer)