required practical 1:enzymes

Question 1

why should the potato paste be smooth?

Answer 1

lumps would affect the surface area and the rate of enzyme-controlled reactions

Question 2

why did the disc rise?

Answer 2

oxygen formed from the breakdown of hydrogen peroxide would form on the surface of the paper disc this would become less dense causing the disc to rise

Question 3

how would you calculate the rate from an end point reaction?

Answer 3

1/time taken (s)

Question 4

why should smaller intervals be used?

Answer 4

to obtain a more accurate optimum

Question 5

why complete repeats?

Answer 5

for a more reliable mean and the identification of anomalies

Question 6

why is a buffer solution used?

Answer 6

to maintain constant pH (unless its an indicator of the rate of the enzyme-controlled reaction)

Question 7

why would a colour standard be used?

Answer 7

if rate is calculated by the time it takes for the indicator to change colour

Question 8

why are test tubes left in a water bath for 10 minutes before the enzyme is added to the substrate?

Answer 8

to equilibriate/reach the temperature of the water bath)

Question 9

suggest some improvements

Answer 9

• use a buffer solution to prevent changes in pH

- use a thermostatically controlled water bath