1. Proteins  Organic compounds made of C, O, H, N and S  Building blocks – 20 different amino acids  Peptide and Polypeptides: Dehydration (Condensation)/ Hydrolysis Reactions

2. 20 Amino Acids

3. Amino Acids * color sheet Which part of this structure gives an amino acid its uniqueness? a. amino group b. side chain c. carboxyl group d. central carbon Review https://www.wisc-online.com/learn/natural- science/chemistry/bic007/peptide-bond-formation

4. www.rand.org/.../Rosetta/images/Proteins.gif Protein Structure *pipe cleaners

5. 4 Classes of Protein Structure 1. Primary Structure -chain sequence of amino acids Phenylalanine

6. b. Pleated Sheet a. alpha helix The Secondary Structure is a. hydrogen bonds making alpha helix and pleated sheets b. chain of amino acids c. chain of monosaccharides d. folded chains of many amino acids

7. 3. Tertiary Structure- 3. Tertiary Structure-Attractions between alpha helix and beta sheets folding onto each other Hydrophobic interactions Disulfide bridges (bonding of 2 cysteine molecules)

8. 4. Quarternary Structure- more than one amino acid chain Ex: Hemoglobin (transport protein)

9. Functions of proteins (directly related to the shape of the protein)  Contraction of muscles  Hormones (signals our cells)  Receptors (found on surface of cells)  Carriers (oxygen to cells)  Antibodies (fight off invaders)  Enzymes

10. FUNCTIONS LET’S REVIEW ON THE BOARD The following is what gives a protein its particular function. a. polarity a. polarity b. shape b. shape c. activation energy c. activation energy d. number of substrates d. number of substrates

11. Enzymes Enzymes - catalytic organic molecules  Lock & Key model  Induced fit model  Enzyme Reactions – temperature & pH dependant

12. Enzyme Specificity  Enzymes are nature’s catalysts  Proteins or RNA  Are reuseable  Generally catalyze only one reaction  Enzyme-substrate complex  Substrate – reactant(s) an enzyme acts on  Active site – where substrate binds to the enzyme; has a specific shape created by folds

13. This enzyme model is an example of lock and key or induced fit. a. lock and key b. induced fit

14. Induced Fit Model What happens to the enzyme after the product leaves? a. retains the shape of the substrate b. does not change at all c. goes back to its original shape d. keeps the shape of the product

15. Factors that affect enzyme activity 1. Temperature – optimal temperature at which rate of reaction in fastest 2. pH – optimal pH at which rate of reaction is fastest

16. Denaturation  Protein loses structure due to some other outside compound or stress - adding acid or base - adding acid or base - change in temperature - change in temperature - large amounts of certain chemicals - large amounts of certain chemicals  Enzymes will not function  May or may not be reversable Ex: eggs and meat

17. Denaturation

18. Closing  1. What is the building blocks of proteins?  2. What are 2 functions of proteins?  3. What controls the function of a protein?  4. Explain what an enzyme is?  5. Why is it important for your body to maintain its internal temperature?  6. What does it mean for an enzyme to be denatured?

19. Animated Denaturation  http://highered.mcgraw- hill.com/sites/0072943696/student_view0/ chapter2/animation__protein_denaturation.html http://highered.mcgraw- hill.com/sites/0072943696/student_view0/ chapter2/animation__protein_denaturation.html http://highered.mcgraw- hill.com/sites/0072943696/student_view0/ chapter2/animation__protein_denaturation.html

20. Nucleic Acids  Very large & complex molecules  Store hereditary information for cells  DNA & RNA  Building block: Nucleotide  A nucleotide contains a Phosphate Group Phosphate Group 5 – C sugar 5 – C sugar Nitrogen Base Nitrogen Base

21. Differences between DNA and RNA DNA  Double stranded  Deoxyribose sugar (5C) Nitrogen bases  Thymine  Adenine  Guanine  Cytosine RNA  Single strand  Ribose sugar (5C) Nitrogen bases  Uracil  Adenine  Guanine  Cytosine

22. Nucleic Acid www.steve.gb.com/.../nucleotides/ssRNA.png