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Hydrophobic molecules

  1. Jan 29, 2009 #1


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    I'm currently studying cell biology, and I'm reading about the hydrophobic parts of the plasma membrane of the animal cell. But I'm wondering, what exactly makes a molecule hydrophilic or hydrophobic? What is the chemistry behind it, and how can I tell which molecules are which? I know that lipids and certain proteins are hydrophobic, but I can't understand why.

  2. jcsd
  3. Jan 29, 2009 #2


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    When a molecule (or a part of a long molecule) is polar (i.e., it has a significant dipole moment), it can attract a water molecule through a dipole-dipole interaction. That is usually what makes it hydrophilic.
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