Warm Up 1.What is the monomer for nucleic acids? 2.What is the function of a carbohydrate? 3.Give one function of a protein? 4.What is the name of the lipid molecule found in the cell membrane? 5.Lipids are afraid of water. What word describes this characteristic? 6.Carbon based compounds come from living organisms and are called ___________

Food Testing for Organic Compounds Iodine (Lugol’s): test for starches (Polysaccarides) –Positive test: will see a color change Biuret’s: test for proteins –Positive test: will see a color change Benedict’s: test for sugar (Mostly monosaccarides) –Positive test: will see a color change Brown Bag: test for lipids –Positive test: will see a translucent appearance on bag

ENZYMES

*Enzymes* A protein that speeds up chemical reactions in the body

*Catalyst* modification or speeding up of a chemical reaction A chemical reaction occurs when some starting material(s) are changed into some desired ending material(s) Ex. You want to make JELLO-- Starting materials (REACTANTS)  Ending materials (PRODUCTS) Water + Gelatin Powder + Heat  JELLO

Chemical reactions need help to get started. An enzyme can be that helper! (I.e. the catalyst)

Let’s see what a chemical reaction looks like on a graph: Image from: Pearson Education Inc, publishing as Pearson Prentice Hall. All rights reserved REACTANTS PRODUCTS ACTIVATION ENERGY Label your graph!

*Activation Energy* the energy required to begin a chemical reaction

Image from: Pearson Education Inc, publishing as Pearson Prentice Hall. All rights reserved Enzymes help chemical reactions happen faster by DECREASING the ACTIVATION ENERGY

How does the enzyme physically do this? Key words: Substrate: the material that an enzyme attaches to (usually your REACTANT) Active site: the site on the enzyme where the substrate attaches

Draw this next slide on the back of your note sheet!!

PROTEINS CAN BE ENZYMES SUBSTRATE (Reactants) ENZYME-SUBSTRATE COMPLEX PRODUCTS ENZYME Unchanged & Reusable ENZYME Image modified from: Arrow: Active site: where substrate and enzyme bond

ENZYMES _____ like a _______________ to only _________of _________. Enzymes are ___________ by the reaction and ___________ LOCK AND KEY REUSABLE UNCHANGED FIT ONE KIND SUBSTRATE *Lock & Key Model*

Warm Up 1.What are the starting materials in a chemical reaction called? 2.What type of organic molecule is an enzyme? 3.What do we call the area on an enzyme where the substrate binds? 4.What is the monomer for a lipid? 5.What does an enzyme do to the activation energy of a chemical reaction? Does this make the reaction happen faster or slower?

2 FACTORS THAT AFFECT ENZYME ACTIVITY __________ & ______________ Conditions that are TOO ACIDIC or TOO HOT cause proteins to ________ or _________ pH temperature Break down DENATURE

pH The pH scale measures how acidic or basic a substance is is an acid 7 is neutral (water) is a base

Denaturing _______ the _______ of the ______________ so enzyme ______________ to ____________ Image modified from: _______________ (keeping pH and temperature constant) is ______________ for maintaining ____________________ HOMEOSTASIS changesshape ACTIVE SITE CAN’T BIND SUBSTRATE IMPORTANT ENZYME FUNCTION

Homeostasis = “balance” All systems on earth want to maintain some form of homeostasis or balance. Keeping pH and temperatures balanced allows enzymes to work best EXAMPLES OF Homeostasis...

Many enzyme NAMES end in _____ and the beginning of the name tells what it does DNA Polymerase= “polymerizes” joins monomers to make DNA -ASE

Warm Up 1.What do most enzymes end in? 2.What is homeostasis? 3.What 2 things can cause an enzyme to get broken down? 4.What word describes what occurs if an enzyme gets too hot. 5.Identify whether the following substances would be considered an acid, base, or neutral: pH=12, pH=3.2, pH=6.5, pH=7, pH=8