Final answer:
The negative control in an enzyme lab is the group with no enzyme, which demonstrates the base reaction rate without enzymatic influence.
Step-by-step explanation:
In an enzyme lab, the negative control is best described as the group with no enzyme. This is because a negative control is meant to show what happens when the experimental factor is not present. In the case of enzyme experiments, the negative control would demonstrate the base reaction rate without the catalytic action of the enzyme.
The purpose of a negative control is to provide a benchmark against which the effects of the enzyme can be measured. Without an enzyme, we expect no enzyme activity, and thus, no catalyzed reaction should occur. It is a critical part of the experimental design to ensure that the observed effects in the experimental groups are indeed due to the presence and activity of the enzyme.
Moreover, a negative control helps to identify any nonexistent or background activities that could be wrongfully attributed to the action of the enzyme. This control group confirms that the substrate alone does not produce the same results as when the enzyme is present.