Department of Biological Sciences
Frequently Asked Questions About Biology from GS students & Transfer Students
Last update 08/28/2017

Note: Course prefixes (C, F, etc.) were changed in July 2016. The old prefixes are used below. The current prefix that replaces both C and F is 'UN.' What is referred to below as C2005/6 is now called UN2005/6 and what is referred to below as F2401/2 is now called UN2401/2.

Q1: What should I take first, biology or chemistry?

Take general chemistry first. See Q3 for the rationale.

Q2: I am premed, and never took college level bio before. What biology class should I take?

If you are a postbaccalaureate student, or a continuing education student, you should take Bio. F2401-F2402. If you need to fulfill the lab requirement for medical school, you should take the lab Bio W2501. You can take the lab either term; we advise taking it after you complete F2401.

If you are a CC or GS undergraduate, you should take Bio C2005-2006 instead of F2401-2402. You do NOT have to take W2501. There are many other ways to fulfill the lab requirement for the major -- see the major requirements page for details.

Note that chemistry is a prerequisite for Bio C2005 or F2401, so you should take general chemistry first. (See Q3 for the rationale behind this.)

See Q5 for details of C2005 vs. F2401. If you have a problem with the number of points, and need to take the 'other class' for more or less points (4 for C2005 vs 3 for F2401) please contact the DUS, Dr.  Mowshowitz, dbm2 at

Q3: Why do I have to take chemistry before biology?

A3: There is a big difference between most college science courses and most high school science courses. In high school, you are usually expected to memorize the basic facts and principles. In college, you are expected to learn the facts in much more detail and you are also expected to understand the principles in much greater depth (this is usually the hard part). This means (in practical terms) that on exams you are asked to apply the principles that you have learned to solve problems and to explain totally new situations. This is just as true of biology as it is of physics and chemistry -- college biology is an experimental science, not a descriptive science. If you jump straight into Biology C2005/F2401 without a year of college chemistry to help you "rev up" you are likely to find the biology overwhelming.
It also pays to take chemistry first for another reason. Most students who take biology need to take chemistry (eventually). If you are going to take chemistry anyway, you might as well take it first so that the molecular parts of bio will make more sense. Biologists use chemistry as language, the way physicists use math. You can explain physics without math, but it takes a lot longer and the explanations are not as satisfying, or you have to teach the math as you go along. So it is simpler to just do the math first and the physics after. Similarly, it makes more sense to do the chemistry first and the biology second.

Q4: I took introductory biology somewhere else. Should I start with C2005/F2401or should I skip C2005 and start with a higher level (3000 level) course?

A4: Transfer students are required to start with C2005/F2401.  (For the difference between the two courses see Q5.)   Intro bio here is required because most students in the past who skipped it found themselves struggling in upper level (3000 level) courses. If you repeat a year of intro bio, you will still receive transfer credit toward graduation for the year of intro you took elsewhere.  However, the previous intro will not count toward your bio or bio related major at CU.  There are exceptions, but they must be approved in advance by an advisor from the biology department. If and only if your intro course was at a rigorous institution, and included a heavy dose of genetics and biochemistry, AND you did well (& remember it), you may be able to skip C2005. If you learned a lot of cell biology & physiology, you may be able to skip C2006. However, in virtually all cases, you will need to take intro bio here. Why? Because C2005/C2006 goes deeper and demands more thought and application of knowledge than the usual introductory college bio course (or AP course). The course covers less topics than usual, but each topic is covered in great detail. There is more stress on problem solving and less on memorization. To make the nature of C2005/6 clearer, you can look at the old exams & other course material on the web page for the course (F2401/C2005) or look at the Learner's Manual (which consists mostly of old exam questions). A recent edition of the Manual (aka Problem Book) should be available in the science library. If you look at all the available material, and still believe you should be able to skip C2005/6, you need to get written permission from an advisor in the biology department.  Only students who have taken an unusually rigorous intro course elsewhere will be granted exceptions. If you plan to ask for an exception, we suggest you register for either C2005/F2401 or a 3000 level course and attend both courses for the first week of class. Once you decide which course is the right level, you can drop or add courses as necessary.

Q5: What is the difference between Bio C2005 and Bio F2401?

A5: Short answer: Not much -- there is a single web site for both classes.

Long answer:
The lectures in Bio C2005 and F2401 are identical and the overall work load in the two courses is the same. However the amount of time a student is required to spend in class is different. This is because C2005 has required recitations (with weekly quizzes) and F2401 has optional recitations (no quizzes). Because of the required recitation, Bio C2005 is 4 points while Bio F2401 is 3 points. The same similarities and differences apply to Bio C2006 vs. F2402.
F2401 has optional recitations because it is assumed that many adult students:
    (1) have less time available to attend recitations because of jobs and family responsibilities,
    (2) do not want to pay for the extra point, and
    (3) have had more practice at pacing themselves and are less likely to allow themselves to fall behind.

The exams in the two courses and the grading scales for the exams are the same - the scale is set using the scores of the C2005 (undergraduate) students. Therefore the exam scores needed to earn an A are exactly the same in each class. However the percentage of A's in each class is often different because the composition of the two classes is not the same. 
Undergraduates in GS &CC should take C2005, and postbacs and special students must register for F2401.
* (Note that all exams in both classes, except the final, are given in the late afternoon or at night.) Students from either class may attend either set of lectures; students can switch back and forth as their schedules change (or they oversleep) or even go twice a day if they want. However, C2005 students must attend C2005 recitations and F2401 students may attend only F2401 recitations. The recitation sections for C2005 are listed separately on the directory of classes -- Students in C2005 must sign up for a section (called C2015, no points) with the registrar. F2401 students do not sign up; times and rooms for the optional F2401 sections will be posted after school starts. All recitations start the second week of classes.

If you need additional information, contact the instructor or see the C2005/F2401 web page which includes notes from last year's lectures, a sample exam, etc.

*If you have a problem with the number of points, and need to take the 'other class' for more or less points (4 for C2005 or C2006 vs 3 for F2401 or F2402) please contact the DUS, Dr.  Mowshowitz, dbm2 at

For additional information for undergraduates, go to the Biology Department Undergraduate Page.

For FAQs for First Year Students and Prospective Students, go to