# Need help with AS AQA biology question

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1. This question is off the specimen paper.
A technician investigated the effect of temperature on the rate of an enzyme-controlled reaction. At each temperature, he started the reaction using the same concentration of substrate.The following graph shows his results.

(b) Draw a tangent on each curve to find the initial rates of reaction.
Use these values to calculate the ratio of the initial rates of reaction at 60 °C : 37 °C.
Show your working. Ratio = ................................ ... :1(2)(c) The answer is 4:1 to 5:1Dont really understand what it means by 'initial rate'.
2. The initial rate would be before either of the graphs "levels off". In the graph for 60°C this would be after about 2 seconds/minutes. So you trace a line from "2" on the axis to where it crosses the graphs. Then you calculate the rate of reaction of each graph at 2 seconds/minutes (I'm not sure what the unit for time is in this case). Compare it and put it into a ratio. Hope that helped!

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