Microbiology

The first point is your point of interest towards subject . If you are interested in pursuing M.Sc. In Microbiology or Biochemistry you can apply for this course.
Following are M.Sc courses which you can apply after completing B.Sc. :-
1) M.Sc. In Microbiology
2) Biochemistry
3) Biotechnology
4) Organic Chemistry
5) Analytical Chemistry
6) Inorganic Chemistry
7) Medicinal Chemistry
8) M.Sc. In Clinical Nutrition and Dietetics
9) M.Sc. In Clinical Research etc.

The eligibility criteria of LPU for M.Sc. Microbiology is given below:
Eligibility criteria: Pass with 60 percent aggregate marks in Bachelor Degree (Applied Medical Science or Medical Science and Allied Medical or Agriculture or Biosciences or Food Science or Medical Lab Technology or Life Sciences or Veterinary Microbiology and Parasitology or Genetic Engineering and Biotechnology or Clinical Chemistry or Public Health and Allied Sciences or Plant Science) or equivalent.
So from above you are eligible for M.Sc. Microbiology course.

I am a student of the university and currently doing my graduation as Electronics Engineer. For pursuing PhD you first have to check the website, if it has PhD opening you have to apply and visit the department.

Microbiology is better because somewhat biotechnology's value and demand have gone down in recent times.