Need help with Biology Lab please.?

[Dave D]

For my Biology lab we have to find out the effect of substrate concentration on enzyme activity. The results were following:

At substrate concentration of 3.00% enzyme works the fastest!
At substrate concentration of 1.50% enzyme works second fastest!
At substrate concentration of 0.75% the enzyme works somewhat fast!
At substrate concentration of 0% the enzyme works the slowest!!!!

How do I explain this because in my hypothesis i stated that the enzyme would work fastest at 0.75% because there is the least amount of substrate that needs to be converted to products. How do I explain my results please help.

If it helps my enzyme was catalase and substrate was hydrogen peroxide.

 

[Gary]

Your hypothesis was incorrect because the rate at which the enzyme works is not simply determined by the amount of substrate.

Instead, the enzyme's speed is determined by the concentration of the substrate in the water. Concentration takes into account both amount of substrate and amount of water. When you made your hypothesis, you didn't take into account the amount of water present.

At higher concentrations, the enzyme encounters the substrate more frequently. At lower concentrations,like 0.75%, the enzyme doesn't come across a substrate molecule that often.