Question

a researcher designs an experiment to investigate the effect of environmental temperature on the function of an enzyme. for each trial included in the experiment, the researcher will add the enzyme and its substrate to an aqueous buffer solution and then measure the amount of product formed over 20 minutes. which of the following must remain the same for all trials of this experiment? a the initial concentration of the substrate b the final concentration of the product c the three - dimensional structure of the enzyme d the temperature of the aqueous buffer solution

Explanation:

In an experiment investigating the effect of temperature (independent variable) on enzyme function, all other factors (controlled variables) must remain constant to ensure results are due to temperature changes. The initial substrate concentration is a controlled variable; varying it would affect product formation independently of temperature. The final product concentration (B) depends on enzyme activity (thus temperature, so it varies). Enzyme structure (C) may change with temperature (denaturation, so it varies). Temperature (D) is the independent variable being tested, so it varies across trials.

Answer:

A. The initial concentration of the substrate