core prac 4

Question 1

What are the independent variables for the enzyme concentration prac?

Answer 1

Protease concentration

Question 2

What are the dependent variables for enzyme concentration prac?

Answer 2

Time taken for enzyme to break down substrate in seconds.

Question 3

What are the control variables for the enzyme conc prac?

Answer 3

• temperature (use a water bath)
• volume of enzyme solution.
• volume of substrate.
• concentration of substrate.

Question 4

What are trypsin and casein?

Answer 4

• Casein is the protein found in milk that gives it its white colour.
• Trypsin is a digestive enzyme that breaks down proteins in the small intestine.

Question 5

What’s the method for the enzyme conc prac?

Answer 5

1. Set up a water bath so temperature can be kept constant.
2. mark an x on one side of the test tube and fill this tube with 5cm3 of casein solution and place it into the water bath with a test tube containing 2cm3 of trypsin.
3. allow both substances to acclimatise for around 3mins.
4. add test tube of trypsin to casein and start the stopwatch, time how long it takes for casein to become transparent (where you can clearly see the x mark)
5. repeat for different concentrations of trypsin.