Word of the day Catalyst: A substance that increases the speed of a chemical reaction AND lowers the amount of energy needed Agenda Latin and Greek Quiz Enzyme Notes Enzyme Study Tool

Review There are four macromolecules Carbohydrates Lipids Nucleic acids Proteins Monomer: amino acids Polymer: polypeptide chains

Let’s study one protein: Enzymes What do Enzymes do? Our body makes many enzymes Enzymes are specialized proteins that breakdown or combine molecules into things our cells need

Catalysts Catalysts: decrease (lowers) the amount of energy needed to start a reaction (activation energy). Enzyme = catalyst

Each enzyme is specific to a reaction Ex: Lipase, Protease, Amylase, Lactase, Sucrase, Catalase (Think of a Lock & Key)

Enzyme Animation http://highered.mheducation.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html

In our lab toothpickase… What represented the enzyme? What represented the substrate? What represented the product?

Induced Fit Model The active site on the enzyme is temporarily reshaped each time the molecules bind Like a lock and a key – that you have to jiggle

How do Enzymes Work? 1. A substrate(s) fits into a active site on the enzyme. 2. The enzyme lowers the energy required to complete the reaction. 3. The product is released by the enzyme.

Factors that affect rates of enzymes: 1. Temperature—work best at body temp. Cold = slow, Hot = denatured (change shape) 2. Concentration of enzyme--more enzymes to do the work = faster 3. Concentration of substrate—more to work on = the slower it goes 4. Competition with inhibitors—other substances (ex: drugs) block active site = they work slower 5. pH—each enzyme has a “best” pH. Out of that range they denature.

In our toothpickase lab….. What did we do that showed enzyme concentration? What did we do to show substrate concentration? What did we do to represent the environment?

Denatured Enzyme Definition: a change in the shape of the enzyme molecule making the enzyme useless or less effective. The substrate no longer “fits” into its’ Active Site. Substrate does not fit enzyme does not work

What does this graph tell you?

Enzyme Animations http://www.kscience.co.uk/animations/anim_2.htm

Can you……..? Define the key words: enzyme, catalysts, substrate, active site, activation energy, products, denatured and substrate specific Describe how an enzyme works. Describe factors that affect enzymes.

An Enzyme in Action Can you describe what is happening here?

enzyme Which would be the substrate and product for this enzyme? Active Site Substrate 1 and products 3/4 Substrate 1 P1 P2 Product Substrate 2 P4 P3

Assignment Make a study tool Must have the word or concept Must have a picture representing the word/concept Must have a written definition of the word/concept