<span>In short, water and oil don't mix because they are two substances with different types of molecules. The structure of oil's molecules makes it hydrophobic, so it won't mix with water's molecules. Water is a polar molecule, meaning the amount of electrons in the hydrogen and electronegative oxygen is unequal....</span>
The southern elephant seal<span> (</span>Mirounga leonine) is one of the two extant species of elephant seals<span>.
Source: Google
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The function of the cell membrane is to protect the cell from unwanted substance, as well as allow needed substances into the cell. So, you could describe the cell membrane as a “security gate”. It’s is selectively permeable meaning that it one lets specific things in and out of the cell.
Chemical formula is the answer