Beta galactosidase is a popular enzyme we used to help break down solutions to simple sugars such as glucose. For instance, ONPG is can be broken down by beta – galactosidase and have a fast-initial rate. In the experiment conducted both ONGP and beta – galactosidase was used to help have a better understanding in chemical reactions and what is too happen to their initial rates when more of the enzyme is added during amount of time. Disaccharides also containing different amounts of solution were added in a different test to determine if they had a similar rate as the reaction with just ONGP and beta galactosidase or if they were different. A spectrophotometer was used to measure the absorbance of ONGP at 420nm, which was timed. All solutions were micro pipetted into cuvettes, adding more of the enzyme 5 times. Calculating afterwards their initial rates. The end results show an increase in initial rate for both ONGP and the other disaccharides added.