An oxygen-binding protein was purified from a mollusk. It was found to exhibit fluorescence,

An oxygen-binding protein was purified from a mollusk. It was found to exhibit fluorescence, which means that it has amino acid residues that absorb light of one wavelength and then emit light of a longer wavelength. Generally, the more exposed these residues are to solvent, the greater their fluorescence intensity. When placed in a deoxygenated buffer solution, the protein’s fluorescence was measured and assigned a value of 1.0. Then the amount of protein fluorescence was measured under various other conditions and expressed relative to the initial measurement. The results are summarized in the table. Which conclusion is supported by these results