Lecturer hours and salary?

I was wondering about lecturers' hours and salary and how this career differs from being a teacher.I am a biology teacher right now, so I know the teacher's average salary is about 42.000$ and working hours are about 40 per week. How does being a lecturer differ? I hold a Doctorate of Medicine, achieved abroad, so I could potentially qualify for teaching in college, that's why I'm interested in better understanding the differences. I look forward to your advice, thank you.