 Enzymes
 Defense (antibodies)
 Storage
 Transport
 Hormones
 Receptor
 Structural
 Contractile and motor proteins
Amino Acids
The Peptide Bond
 Dehydration (condensation) reactions bond the
carboxyl group of one amino acid to the amino group
of another to form a peptide bond.
 A chain of amino acids linked by peptide bonds is
called a polypeptide.
 Polypeptides containing fewer than 50 amino acids are
called oligopeptides .
 Polypeptides containing more than 50 amino acids are
called proteins.
dehydration synthesis
How do proteins get broken down?
H2O
STRUCTURE OF PROTEINS
 Primary
 Secondary
 Tertiary
 Quarternary
Clog blood vessels, impeding blood flow
Denaturation
 Environment changes affect the structure of proteins
 Bonds can become weakened or destroyed
 Protein will unravel and lose its shape
 The protein becomes inactive and will not function
 Rarely the protein can return to shape once the
denaturing substance is removed.