1. Add to your vocab sheet & Correct Inv. 4.4

2. Proteins or Polypeptides Examples Nuts, meat (muscle), beans Uses Muscle, hair, nails, skin, enzymes Made from Amino Acid chains (polypeptides) that can be thousands of amino acids long There are only 20 amino acids in nature! -peptide

3. Enzymes Large, complex proteins Help speed up the rate of chemical reaction (catalyst) –ase word ending (Lactase breaks down lactose) Activity varies with pH and temperature changes Can be denatured by extreme heat (shape is changed) Eg. Think about an egg before and after it’s cooked. The egg proteins are denatured as it cooks. Can be reused over and over again “Lock & Key” Model Active Site: attracts and holds only molecules that have the right shape Substrate: molecule that is changed by the enzyme – must have the right shape

4. Enzymes Video (click on it)

5. Example: Lactose Intolerance Lactose is a sugar found in most milk products Lactase is an enzyme that breaks down lactose People who are missing lactase (can no longer produce it) can’t eat lactose unless they get artificial lactase.

6. Example: Lactose Intolerance

7. Investigation 4.4 Review A monosaccharide turns Benedict’s solution from blue to orange after heating. A polysaccharide turns iodine from amber/ yellow to dark blue/black without heating. A disaccharide responds to neither Benedict’s nor iodine.

8. Table 4-1 Results of Tests with Known Carbohydrates Tube Number Carbohydrate Type Benedicts Color After Heating Iodine Color 1MonosaccharideOrangeAmber/ Yellow 2DisaccharideBlueAmber/ Yellow 3PolysaccharideBlueBlue/ Black

9. Table 4-2 Results of Tests with Unknown Carbohydrates CarbohydrateHypothesis (Mono-, Di-, or Poly-) Benedict’s Color After Heating Iodine Color Type of Carbohydrate (after testing) HoneyOrangeAmber/ Yellow Mono – (fructose & glucose) OatsBlueBlue/ BlackPoly- (starch) Table SugarBlueAmber/ Yellow Di- (sucrose) Apple JuiceOrangeAmber/ Yellow Mono- (fructose) Powdered Sugar BlueAmber/ Yellow Di- (sucrose) Maple SyrupYellow/ green Amber/ Yellow Mono- (fructose) some Di- (sucrose)

10. Investigation 4.5 You’ll be using the same testing methods as in lab 4.4 however you’ll do the lab in 3 Parts 1. Part A: Properties of Starch 2. Part B: Properties of Salivary Amylase (enzyme present in saliva – yes someone will be spitting, discreetly into a test tube!) 3. Part C: Properties of Starch Mixed with Salivary Amylase At each Part you’ll test with both Benedict’s (and heat) and iodine (no heat) and record your data.

11. SAFETY! No eating or drinking during the lab! Iodine and Benedict’s can stain and are both toxic! Wear aprons and goggles if you choose. If you are the generous saliva donor, you will be the only one to handle, and wash your test tubes!

12. Set up Part C – 1 st ! (it needs to sit for 15 minutes minimum!) READ the background info to help you with the DQ and Analysis Questions Quiz on both labs (open notes/open lab) Thursday!