Starter: 10/7/14
• Compare the structure of the four
biomolecules shown below.
– The arrangement of the elements
– The type of element
– The molecules are the building blocks of life
– The functions of the biomolecules
Structure  Function
Nucleic Acids and Proteins
Structure  Function
• An important theme in biology is that
structure leads to function
• Structure is especially important in proteins
and nucleic acids
Nucleic Acid Structure
• Nucleic acids are
composed of
nucleotides,
which contain
carbon, hydrogen,
oxygen, nitrogen,
and phosphorus
atoms
Nucleic Acid Structure
• The sequence of
nucleotides
determines an
organism’s
genetic code
Protein Structure
• Proteins are composed of amino acids
• All amino acids contain carbon, hydrogen,
oxygen, and nitrogen
Protein Structure
There are 20
different amino
acids, which
differ in their R-
groups
(variable
groups)
Peptide Bonds
• Peptide bonds join amino acids together to
form a protein
Protein Shape
• Proteins can have up to four levels of
structure
Protein Structure
• Primary Structure: the
number and sequence
of amino acids
• The sequence of amino
acids ultimately
determines a proteins
structure
Protein Structure
• Secondary Structure: two basic threedimensional shapes
– Helix
– Pleat
Protein Structure
• Tertiary Structure:
globular or fibers
Protein Structure
• Quaternary Structure: protein combines with
other proteins
Biomolecules and the
Origins of Life
• Why are biomolecules important to us?
• Miller-Urey Experiment