Kajal, there are 2 things to it. There is no subject such as Zoology in MBBS curriculum. So with M.Sc B.Ed, you cannot teach in any Medical College. The other thing is that you should have studied MBBS to teach in a Medical College. You should have studied atleast MBBS and put up atleast 8-10 years of experience before you are hired as a Professor. And you can have a M.Sc degree in any of the non surgical subjects of MBBS curriculum and put up atleast 5-8 years of experience before you are hired as an Assistant Professor. But to study a subject in your Master's you should have had that subject in your Graduation. For example, if you want to become a teaching faculty in Anatomy, you should either have studied Anatomy at PG level or should have had Anatomy as one of your subjects in your Graduation and then study M.Sc Anatomy and put up the relevant required experience.