Transcript Organic Chemistry and Enzymes
Organic Reactions and Enzymes
Warmup
(9/22)
Watch the video and answer the following questions http://www.youtube.com/watch?v=9X-BtcjOTus What is the purpose of pasteurization?
Describe two types of pasteurization.
Why is it important to eat whole (raw) fruits and vegetables?
Why are preservatives added to juice, even after pasteurization?
Gather Data for Enzyme Lab
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Make qualitative observations Gently pour off pineapple into GARBAGE CAN (NOT INTO SINK!!) Take measurements Record data for the control Calculate the rate of degradation Write a conclusion in your lab book
Warmup (9/27)
Results from McMush unknown food samples:
Food Sample #1 Food Sample #2 Food Sample #3
Sausage Eggs Coffee Pancakes Butter Syrup Hashbrowns Apple Juice Oatmeal with maple and fruit Water What organic compounds would you expect to be present in each of these food samples?
Did your results match these expectations? Revise or add to your conclusion questions based on this information (specifically #4).
Chemical Reactions
Changing of one set of chemicals into a new set of chemicals A chemical change Always involve the breaking of chemical bonds and/or the formation of new bonds Examples: CH 4 + O 2
2H 2 + O 2
CO 2 + H 2 O (
This is not balanced) 2H 2 O
Energy in Reactions
Reactions can release or absorb energy Reactions that release energy (exothermic)can occur spontaneously, however, many need
Activation energy
Activation energy is energy needed to get a reaction started
Energy in reactions cont.
Chemical reactions that absorb energy (endothermic) generally need much activation energy
Enzymes
Biological catalysts (get reaction started!) Speed up the reaction by lowering the activation energy (Catalysts).
Enzyme action
Enzymes have a particular shape.
Provides a “binding site”, a place where the substrate (reactant) fits in like a lock and key
then the reaction happens
Shape of enzyme’s binding (active) site is very specific —only fits one substrate
Enzymes are Sensitive!
Specific conditions are required for an enzyme to function: Most will only work within a particular range of: Temperature pH (acidity) At high temperatures, an enzyme may degrade (break down).
(Think pineapple and Jell-O)
This helps to regulate enzyme function Enzymes only cause the reaction to happen when the conditions are right. Human body?
How enzymes are named
Each is usually named for the reaction it catalyzes Protease = breaks down protein Anhydrase = removes water If you know the name, you can often figure out the function!
pH Scale
• Let’s get pHunky
You may know…
• Chemists measure how acidic or basic a substance is with… The pH scale • Acid and base strength is measured on a pH scale that ranges from 0 to 14 • Neutral solutions have a pH = 7 • • Acidic solutions have a pH < 7 Basic solutions have a pH > 7
• • •
Acids
These substances have extra H+ ions Below 7 = acid pH indicates the amount of Hydrogen ions in a solution It’s the p OWER of H ydrogen, phools!
• • •
Bases
These solutions have fewer H+ in the substance (and more OH- ions) Base is anything > 7 Aka alkaline • Neutral substances= 7
pHun with the pH scale
Just remember this brothers and sisters: ABBA
Why is this chemistry important in biology class?
• Your body HOMEOSTASIS!!!!!!!!
– Stomach acids help digest food – Blood – pH of about 7 (neutral) – Enzymes function only at specific pH
Why is this chemistry important in biology class?
• Environment – Acid rain – Water pollution
Acid Rain Effects
Application: How does pH affect an enzyme?
• Look at “Analyzing Data” section on page 51 in your textbook.
– Answer questions #1-6
Homework
(due Wed 9/28)
Write out the answers to all Chapter 1 and 2 Learning Targets Must write in complete sentences Do this in your lab book, after the McMush conclusion questions