Download Enzyme Action Stations Lab: Procedures: Follow the directions at

Enzyme Action Stations Lab:
Procedures:
Follow the directions at each station for testing the effects of different variables on the
reaction rate of the enzyme peroxidase.
STATION 1
Problem: Are enzymes affected by heat?
Background: Enzymes are chains of amino acids (proteins.) They work like a lock and
key. If enzymes are exposed to extreme heat, then they “denature” - change shape. If
the enzyme denatures, then the enzyme-key will no longer work in the substrate-lock.
Procedure:
 Place a small piece of cooked avocado in a Petri dish, and a small piece of
raw avocado on the another Petri dish.
 Place 10 drops of hydrogen peroxide on the avocado.
 Observe for enzyme activity by looking for bubbles.
 Rate the amount of oxygen bubbles produced on a scale of 1 to 5?
 Record your data in the chart.
STATION 2
Problem:Can enzymes be reused?
Background: Enzymes are chains of amino acids (proteins.) They work like a lock and
key. The substrate is the lock and the enzyme is the key. Enzymes are reusable, just
as you can reuse your house key to open the door to your house over & over again.
Procedure:
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STATION 3
Place a small piece of avocado in a Petri dish.
Place 10 drops of hydrogen peroxide on the avocado.
Observe for enzyme activity by looking for bubbles.
Rate the amount of oxygen bubbles produced on a scale of 1 to 5?
Record your data in the chart.
Remove the piece of avocado you just tested to another Petri dish.
Place 10 drops of hydrogen peroxide on the avocado.
Observe for enzyme activity by looking for bubbles.
Rate the amount of oxygen bubbles produced on a scale of 1 to 5?
Record your data in the chart.
Problem: Are enzymes affected by pH?
Background: Enzymes are chains of amino acids (proteins.) They work like a lock and
key. If enzymes are exposed to extreme pH, then they “denature” - change shape. If
the enzyme denatures, then the enzyme-key will no longer work in the substrate-lock.
Procedure:
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Place a small piece of avocado soaked in acid (vinegar) in a Petri dish.
Place 10 drops of hydrogen peroxide on the avocado.
Observe for enzyme activity by looking for bubbles.
Rate the amount of oxygen bubbles produced on a scale of 1 to 5?
Record your data in the chart.
Place a small piece of avocado soaked in an alkaline/base (baking soda) in
a Petri dish.
Place 10 drops of hydrogen peroxide on the avocado.
Observe for enzyme activity by looking for bubbles.
Rate the amount of oxygen bubbles produced on a scale of 1 to 5?
Record your data in the chart.
STATION 4
Problem:How does surface area affect enzyme reactions?
Background: Surface area refers to the amount of surface exposed. For example, a
solid block of ice has less surface area than the same amount of crushed ice. The more
surface area is exposed, the more enzymes that are available to react.
PROCEDURE:
 Place a small amount of ground avocado in a Petri dish.
 Place 10 drops of hydrogen peroxide on the avocado.
 Observe for enzyme activity by looking for bubbles.
 Rate the amount of oxygen bubbles produced on a scale of 1 to 5?
 Record your data in the chart.
STATION 5
Problem: Are enzymes specific?
Background: Enzymes are chains of amino acids (proteins.) They work like a lock and
key. The enzyme is the key that unlocks the substrate. Remember, only one key can
fit one lock.
Procedure:
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Place a small piece of avocado in a Petri dish.
Place 10 drops of vinegar substrate on the avocado.
Observe for enzyme activity by looking for bubbles.
Rate the amount of oxygen bubbles produced on a scale of 1 to 5?
Record your data in the chart.