Now, what about enzyme activity? Well, the enzyme activity we spoke about before and we said that the enzyme activity tells us the ability of that enzyme to basically promote a specific type of reaction within that sample. And the units are micromoles per minute. So the classically units are micromoles per minute which is equal to a unit. But nowadays we also use moles per second. So what the enzyme activity tells us is how many milli or how many micromoles of that product that is produced by the enzyme per minute or how many micro moles of the substrate is transformed by that enzyme every single minute.