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
Dec 28, 2015
Word of the day
• Catalyst: – A substance that increases the speed of a
chemical reaction AND lowers the amount of energy needed
AgendaLatin and Greek QuizEnzyme NotesEnzyme 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
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 describewhat is happening here?
ActiveSite
Substrate 1
Substrate 2
P1 P2
Product
P3 P4Which would be the substrate and product for this enzyme?
Substrate 1 and products 3/4
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