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Ph.D. Degree requirements

Credit Hours

Admissions ≤ Aug-2015

There is no minimum number of hours required for a Ph.D. degree. Most students in our Ph.D. program take an average of 24-30 credit hours. Plans of study with substantially less credit hours will need special justification for approval.

Admissions ≥ Aug-2016

You must complete the selected Ph.D. Course Rerquirements before the end of your second year.  This will be on average 21 credit hours


At least one-third of the total credit hours used to satisfy degree requirements must be earned (while registered for doctoral study) in continuous residence on the Purdue campus where the degree is to be granted.


Teaching Requirement

Ph.D. students must teach for one semester with direct contact with students.

NOTE: All international students whose native language is not English must be Speak Certified prior to holding a TA assignment that fulfills the requirement.


Seminar Requirement

Each Ph.D. student is required to present a satisfactory seminar in each of two student participation seminar courses (normally BIOL 696). Only seminars in which the student researches, in depth, a topic outside their own research field and presents it in a reasonable, coherent manner can be used to meet this requirement.


Grade Index Requirement

Only grades of A, B, or C are acceptable on a plan of study for 500 and 600-level courses. An Advisory Committee may require a higher performance than C in certain courses. A grade of A or B is required for 400-level courses.

The student is expected to maintain a cumulative index of 3.0 Should the student fail to perform at a satisfactory level he/she may be asked to discontinue graduate study at Purdue University.


Residence Requirement

Six units of residence are required for Ph.D. degrees. Fifteen semester hours registration equal one unit of residency.


Time Limitation

The College of Science has established a policy of seven (7) years from entry into the graduate program (i.e., 14 semesters plus the intervening summers - plus one additional summer to finish if necessary) be the maximum time allowed to complete the Ph.D.

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