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. 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

3. 20 Amino Acids

4. 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

5. Protein
Structure

6. 4 Classes of Protein Structure
1.Primary Structure-chain sequence of amino acids
Phenylalanine

7. 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
b. Pleated Sheet
a. alpha helix

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

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

10. FUNCTIONS LET’S REVIEW ON THE BOARD
The following is what gives a protein its particular function.
a. polarity
b. shape
c. activation energy
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
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
- change in temperature
- 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

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

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

22. Nucleic Acid