If you want to study the "really little critters" in the world of biology at a professional level, you will want to get a doctorate in microbiology. Microbiology is the study of microscopic organisms that focuses on three divisions: unicellular (single cell), multicellular (cell colony), or acellular (lacking cells). A doctorate in microbiology allows you to research, teach or work in a number of sub-disciplines that include parasitology, virology, bacteriology and mycology.

High School Classes

Some high school students know exactly what they want to do when they grow up and are prepared to work hard towards reaching their career goals. If you are in high school and want a doctorate in microbiology, now is a great time to get started. You will want to take as many biology courses as possible, especially AP classes. Some high school biology classes may dedicate so many days out of the curriculum focusing on microbiology, where students may learn microbiological techniques like isolation of bacteria from food, preparation of agar plates, serial dilution and plating. If you can find your way into such a class, ask your teacher how to identify unknown bacteria and the steps needed to pinpoint the right antibiotics to use against them.

Undergraduate Degree

As you will be hard pressed to find a college or university that offers a doctorate in microbiology without the requirement of first having a B.A. or B.S. degree in the field, you will naturally want to earn an undergraduate degree in microbiology or related field. Undergraduate degrees in microbiology provide the education and skills needed to enter a doctorate program and engage in advanced research. These degree programs provide core courses like the ones offered from Indiana University, which include ecology, developmental, environmental, molecular and cellular microbiology. General courses are also offered and typically include inorganic and organic chemistry, calculus, humanities and social science. These core and general classes will provide the education required to approach microbiology work at the doctorate level.

Take the GRE

Almost every single college and university requires students to take the Graduate Record Examination (GRE) before entering a doctorate program in any subject. This examination lets college admissions boards know how knowledgeable an applicant is in various areas such as verbal reasoning, quantitative reasoning and analytical writing. Most schools require applicants to have a certain test score before they are considered for admission. GRE study books are available to help students better prepare for the exam by offering approaches to various question types, and many of them offer practice exams to help improve scores.

Earning a Doctorate

Not all doctorate programs in microbiology are identical but most require students to take advanced specialty courses before earning their degree. Georgetown University's microbiology doctorate students take Advanced Techniques in Microbiology and Immunology and attend a Microbiology Seminar. It is also protocol for many universities, including Georgetown, to assign doctoral students an adviser who helps plan their academic program according to the student's individual needs and career goals. Before most doctoral students can earn their degree, they must also conduct research and present a written thesis on their research.