Here it says that we need to label all alpha amino acids. Let's start with A. Alright. So we know that our carboxyl group is this carboxylic acid group right here. We're going to say here that our amino group is the nitrogen-containing group here. That would mean that in the middle between them is our alpha carbon. This is our alpha carbon. It is connected to a hydrogen that we know, and then look, we have this other group here, something we haven't seen up to this point. This has to be our R group. So this would label this alpha amino acid. Let's go to the next one.

We have our carboxylic acid, we have our amino group. Remember the carbon that connects them together would have to be the alpha carbon. So, here's our alpha carbon here. We would say in this case, this one's a little bit different, a little more complex than what we're used to seeing. We're going to say as a result of this, that this one should have this amino group attached directly to the alpha carbon here, but it does not. So this would represent not a traditional alpha carbon because the amino group should be directly attached to my alpha carbon. Right? So here we'd say that this one deviates from what we're used to seeing.

If we go to C, for C, we have our carboxylic acid group here. We have our amino group here. The carbon that connects them together is our alpha carbon. It is connected to an H, which would mean that this part which we haven't seen so far has to be a unique R group. Remember, there are 20 different types of unique R groups here. Right? So this is what we can say in terms of this. Alright, so we'd say that A and C represent traditional alpha amino acids. B, we see that the alpha carbon in the middle is not connected to an amino group, so it doesn't relate to our standard 20 amino acids that we're going to be seeing. Alright, so B deviates from what we would classify as an amino acid.