DNA

1. DNA

2. Proteins: Multipurpose molecules

3. insulin hemoglobin collagen (skin) Proteins Examples • muscle • fingernails, claws • skin • hair • enzymes • example: pepsin • hormones • example: insulin

4. Proteins • Function: • many, many functions • hormones • insulin • movement • muscle • immune system • protect against germs • enzymes • help chemical reactions

5. H | —C— | H amino acid amino acid amino acid amino acid amino acid – – – – C—OH —N— O || H Proteins • Building block = amino acids • 20 different amino acids variable group

6. amino acid amino acid amino acid amino acid amino acid Amino acid chains • Proteins • amino acids chained into a polymer • Each amino acid is different • some “like” water & dissolve in it • some “fear” water & separate from it

7. Water-fearing amino acids • Hydrophobic • “water fearing” amino acids • try to get away from water in cell • the protein folds

8. Water-loving amino acids • Hydrophillic • “water loving” amino acids • try to stay in water in cell • the protein folds

9. collagen 3-D protein structure • Proteins fold & twist into 3-D shape • that’s what happens in the cell! hemoglobin growthhormone pepsin

10. Its 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 = “denature” • temperature • pH (acidity) unfolded“denatured” folded

11. Let’s eat some Proteins!