Well, the urea cycle gives us a way to transform a toxic byproduct of amino acid metabolism, namely ammonium, into less toxic form urea that can then be mobilized and transported to the kidneys, where the kidneys excrete the urea via urine. So that's what the urea cycle is. Now, let's take a look at the details of this cycle. And let's begin by summarizing the cycle on this side. And then let's take a look at the details of each step. So ultimately, we can break down the cycle into five steps.