Professors may not always check completed homework or even collect it, but they will assume you can perform the same tasks on tests. Teachers remind you of your incomplete work. Professors may not remind you of incomplete work. Teachers approach you if they believe you need help or tutoring. Professors are usually open and helpful, but most expect you to ask for help or tutoring.
Teachers are often available for conversation before, during, or after class.
Professors want and expect you to attend their scheduled office hours. Teachers have been trained in teaching methods to assist imparting knowledge. Professors have been trained in experts in their particular area of specialization. Teachers provide you with information you missed when you were absent. Professors expect you to get from classmates any notes from classes you missed.