. . . . . . . . . "MSH: The parts of a macromolecule that directly participate in its specific combination with another molecule.,CSP: reactive portion of a macromolecule that directly participates in its specific combination with another molecule." . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .