You are dependent on your professor for your grade. Your professor, in turn, is dependent on you for his or her job. Hegel would call this a (n) :

dialectic relationship.

Explanation:

Hegel coined the "Master-slave" dialectic for a relationship that exists where although one holds the power over the other, there is a constant and permanent bond between them. The necessity of depending on the other makes this relationship dialectical.

The slave needs the Lord for granting him the means of survival, and the Lord, in turn, needs the labour done by the slave.

Similarly, students and professors are always relying on the other for keeping the teaching & learning environment healthy, while you can depend on him for grades, the teacher must also foreseek for you well being so he can keep his job.