If you mix yellow and blue paint, you produce green paint. in genetics, this is analogous to

I believe it's genes. Your parents mixed genes to create you.

The answer to this will be from your lab notes/procedure. it would be best to ask another student who participated in the lab as we do not know what was done, what enzyme or if the temperature is celsius or fahrenheit. if i were to guess though i'd say the rate stopped due to enzyme denturing at high temperature