The term "hydrophilic" means these amino acids aren't repelled by water. The hiding score component for hydrophilics still tends to penalize them for not being hidden in the protein's core, however. For example, a histidine on the outside of a protein might have a hiding score of -20.9 points, while nearby histidine pointing toward the core might have a hiding score of -16.2 points. In Foldit, the hydrophilic amino acids are: * Serine * Threonine * Asparagine * Aspartate (aspartic acid) * Glutamine * Glutamate (glutamic acid) * Histidine * Lysine * Arginine