1. Proteins Polymers of amino acid monomers DO NOW: What do you notice about the proteins below?

2. Proteins All Cells (life) are based on the structures and functions of proteins 50 % of dry matter in animals is protein All proteins made from same 20 amino acids

3. Monomers - Amino Acids Made of elements C,H,O,N,S 20 essential amino acids (building blocks of proteins) Combined in 20X10 29 different ways Amino Acids (AA) form long chains called polypeptides

4. Amino Acids Humans synthesize 12 amino acids 8 are essential

5. Essential Amino Acids Not because they are more important to life than the others The body does not synthesize essential amino acids, making it essential to include them in one's diet in order to obtain them.

6. FUNCTION Function (job) of protein is based on its SHAPE! –Shape determined by amino acid sequence –Change one amino acid - can change the shape of the protein and make it useless

7. What do Proteins DO? Storage: Transport: Regulatory: Movement: Structural Enzymes Albumin (egg white) Hemoglobin Hormones Muscles Memmranes, hair, nails, claws, scales, feathers Cellular Reactions

8. SHAPE Hydrogen bonds between amino acids cause the polypeptide chain to fold and twist into very special shapes Proteins can only maintain their shape in a narrow range of pH, temperature, moisture, and other factors LOSS OF SHAPE = LOSS OF FUNCTION!

9. Proteins Nucleic acids (DNA and RNA) contain instructions for making proteins A mutation (change) in DNA or RNA causes a change in the protein sequence (structure)

10. Levels of Protein Structure Primary Structure Secondary Structure Tertiary Structure Quarternary Structure

11. Primary Structure

13. Levels of Protein Structure Fibrous Proteins: Primary - chain (squiggly) –Straight polypeptide chain Secondary - helix (twisted) –Repeatedly coiled and folded Due to Hydrogen bonds Examples –Keratin –Collagen –Sickle cell –Spider web

16. Levels of Protein Structure Globular Proteins: - Polypeptide chains that are folded into compact spherical shapes. Involved in cellular and body functions. Tertiary: Globular (folds back on itself) –Hydrophobic parts end up in clusters at core of protein Quarternary: Complex (looks squiggly, twisted, and folded –Two or more polypeptide chains

17. Primary Secondary Tertiary Quaternary