1: Enzyme concentration affecting the initial rate of reaction

Question 1

Independent variable

Answer 1

Enzyme concentration (trypsin)

Question 2

Dependent variable

Answer 2

change in absorbance per second (rate of reaction)

Question 3

Name the substrate found in milk

Answer 3

casein

Question 4

4 variables that need controlling

Answer 4

substrate pH
volume of substrate
temperature
volume of enzyme

Question 5

What device is used to measure change in absorbance?

Answer 5

colorimeter

Question 6

Over time the solution changes colour from white to _____

Answer 6

colourless

Question 7

Why are comparisons made at the start of a reaction?

Answer 7

There are no limiting factors,

substrate concentration is at its highest and their concentration values are known and thus can be compared

Question 8

If the cuvette used for the reaction was scratched (but the reference cuvette wasn’t) would this give a systematic error or random error?

Answer 8

Systematic error because

it would cause absorbance readings to be higher than the true value for every measurement