Core Practical 1.10 - Enzymes & pH

Question 1

Enzymes & pH

Method:

Answer 1

• Put iodine in each well of a spotting tile.
• Add 2 cm3 of amylase and 1 cm3 of pH 2 buffer to a test tube
• Mix, then add starch solution, then start timer
• Every 10 seconds, transfer a drop of the mixture to a new well of iodine solution (which should turn blue-black).
• Repeat transferring drops every 10 seconds until the iodine solution stops turning blue-black
• Repeat with different pH buffer solutions (from pH 3.0 to pH 7.0).

Question 2

Enzymes & pH

Equipment:

Answer 2

• Spotting tile
• Stopwatch
• Buffer solutions
• Iodine
• Starch solution
• Amylase solution

Question 3

Enzymes & pH

Variables:

Answer 3

• Dependent: Enzyme activity.
• Independent: pH levels.
• Control: Volume and concentration of enzyme