Now, because of this very small H atom, because it doesn't have that ch three group like, let's say this one has, this one is not really labeled as a hydrophobic side chain, but because of its small size, it can easily interact with other hydrophobic side chains and it can also interact with hydrophilic side groups. So Glycine is the smallest amino acid. It is a chiral. And because it's minimally invasive, because of that tiny H atom, it can fit into either hydrophobic or hydrophilic environments. And finally, let's take a look at another special case known as proline. Now, proline is technically a hydrophobic side chain, but because of its special structure of that side chain, we label it as a special side chain.