Which statement best describes the fate of excess amino acids? So, amino acids travel to the kidneys and are excreted in the urine. Here, that's not true. We know that excess amino acids travel to the liver. So this does not work.
Amino acids are stored in the liver for later use as energy when it comes to the carbon skeleton, but not the amino group. Again, remember the amino group is toxic to our bodies. We're going to say that some of it is excreted as ammonium ion through the urea cycle and some of it helps to create other types of nitrogen compounds within our body that we need to utilize, such as nucleotides, other nonessential amino acids, as well as hormones. Carbon skeletons are converted to citric acid cycle intermediates and then back to amino acids when needed. Here, that is not the fate of our excess amino acids, so this doesn't work.
Amino groups of amino acids are removed and converted to urea. Yes, part of the urea cycle. Some of it will be converted into urea through the urea cycle, some of it will be converted into nitrogen compounds. Here, this statement is true. So out of all the options, option D is our final answer.