2. Regents Biology 2006-2007 Proteins: The Multipurpose Molecules

3. Regents Biology Protein Functions  enzymes  structure  transport  cell to cell signals  defense (antibodies)  movement  storage

4. Regents Biology collagen Protein Examples:  Keratin  hair and nail  collagen  protein in skin  pepsin  digestive enzyme in stomach  insulin  hormone that controls blood sugar levels pepsin insulin

5. Regents Biology Protein Monomers = amino acids  Structure  central carbon  amino group  carboxyl group (acid)  R group (side chain)  variable group  20 different amino acids —N——N— H H C—OH || O R | —C— | H Oh, I get it! amino = NH2 acid = COOH

6. Regents Biology Monomer to Polymer = amino acid chains  Proteins are amino acids chained into a polymer (called a polypeptide)  Each amino acid is different  Example some “like” water & dissolve in it  Example some “fear” water & separate from it amino acid

7. Regents Biology

8. pepsin For proteins: SHAPE matters! collagen  Proteins fold & twist into 3-D shape  Different shapes = different jobs hemoglobin growth hormone

9. Regents Biology It’s SHAPE that matters!  Proteins do their jobs, because of their shape  Unfolding a protein destroys its shape  wrong shape = can’t do its job  unfolding proteins called “denaturization”  temperature  pH (acidity)  salt folded unfolded “denatured”

10. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

11. Regents Biology Any questions? Yea…what’s up with that coat? Looks like my cousin