Hydrogen Bonds (for AP120

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Hydrogen Bonds(for AP120 BIO120)
From a chemistry standpoint, some of this is
incorrect or a gross over-simplification, but it
gives you the right idea and serves our purpose
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Hydrogen Bonds

• Are attractive forces between a hydrogen and an
  oxygen or a hydrogen and a nitrogen
• Hydrogen bonds can exists between
• two different molecules--resulting in their being
  held together.
• two different parts of the same
  molecule--resulting in the bending/folding of the
  molecule.
• But hydrogen bonds dont create molecules the way
  that a covalent or ionic bond does.

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Formation of Hydrogen Bond Between 2 different
molecules
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H
Attraction between H N (this is due to polar
charges)
N
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Hydrogen Bond holding two different molecules
together
NOTE This type of bonding also happens between
Hydrogen and Oxygen
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Formation of hydrogen bond within the same
molecule
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Attraction between nitrogen and hydrogen
H
N
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H
N
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H
N
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H
N
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H
N
AGAIN The bond could also be between a hydrogen
and an oxygen
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Comments

• Although individual hydrogen bonds are weak, the
  collective influence of many hydrogen bonds can
  be significant
• The bending of molecules with hydrogen bonds is
  important in molecule shape and function
  (discussed later in class)

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THE END