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Biology practical

Enzymes: amylase and temperature

Time how long amylase takes to digest starch at five temperatures, draw a smooth curve of rate against temperature, and find the optimum.

What you will do

  1. 01Stand a tube of starch and a tube of amylase in a water bath and wait until both are at the bath temperature.
  2. 02Pour the amylase into the starch and start timing.
  3. 03Every 30 seconds, put a drop of the mixture on a fresh well of iodine on the spotting tile.
  4. 04Blue-black means starch is still there. Stop when a drop stays orange-brown, and record that time.
  5. 05Repeat at each temperature, with fresh tubes and a clean tile.
  6. 06Calculate the rate as 1/t, plot it against temperature, draw a smooth curve and read off the optimum.