How do Rappaccini and Baglioni use Beatrice and Giovanni for their own needs in "Rappaccini's Daughter"?

When Giovanni first
speaks with his father's old friend, Professor Baglioni, the professor tells him that Dr.
Rappaccini cares a great deal more about science than he does about people and that he only sees
individuals as potential subjects of his experiments.  However, the narrator implies that
Baglioni has an axe to grind because Rappaccini and Baglioni are at odds professionally and that
Rappaccini "was generally thought to have gained the advantage" in their
disagreements. Therefore, it should not be terribly surprising when Baglioni continues to try to
arouse Giovanni's suspicions...