Biology CLEP
Free Study Guide

Free Biology CLEP Study Guide

Name of Exam: Biology CLEP

Number of Questions:115

Time Limit: 90 Minutes

ACE Recommended Passing Score: 50

Practice Test Available?: Yes - Click here

Cost: $80 + Sitting Fee (Usually no more than $20) at your testing site. Military can take CLEPs for free with Tuition Assistance. Check with your Educational Officer!

Difficulty 1-5 : 3 (One being the easiest, and five being the hardest)

Exam Description:

The Biology CLEP covers the knowledge you would learn in a one-year college biology course. It covers the areas of organismal, populational, and molecular/cellular biology. This is an extremely broad exam that goes into depth on each of the before-mentioned areas.

Personal Thoughts:

I'm not going to mislead you; the Biology CLEP is a monster. Though this is a level 3 exam on the CLEP Difficulty List, it's at the very end of the level 3 category. The reason most people find it so difficult is the amount of information it requires you to know. This exam covers the Biology knowledge you would normally learn in an entire year. Not a semester like most CLEP's, but a year.

So there's the bad, now let's talk about the good. Since this covers so much information, the CollegeBoard recommends you get six credits for a successful pass. Most schools follow along with this recommendation, though you should always check with your advisor to make sure your school does as well. The second bit of good news is that the Biology CLEP is perfectly passable if you're willing to dedicate the time and energy to preparing for it.

This is one of those CLEP's that I highly recommend subscribing to InstantCert Academy if you haven't already. Not only do they have over 800 flashcards for the Biology CLEP (and you should study every one), but the Specific Feedback thread has six pages of detailed exam information from forum members who have already taken and passed the exam.

I'm going to do my best to provide you with enough free resources to pass, but my recommendation is to use InstantCert for this exam as well. As with all of the six credit CLEP's, the sheer amount of information is daunting unless you have some targeted study material.

Exam breakdown:

According to the College Board website, the Biology CLEP exam is broken down as follows:

34%Organismal Biology
33%Molecular/Cellular Biology
33%Population Biology

Areas of Study

I'm still experimenting with the best way to cover the needed material. I'm going to break down the percentages above with the topics that fall under each category. This should allow you to decide what you need help with, and only study those areas in which you feel a little weak. Less wading through masses of resources, and more targeted studying.

If you like this style, please let me know via the "Contact Us" form. The end goal here is to give you the information in the most helpful manner.

Alright, here we go:

Organismal Biology (33% of the exam)

Plant related material

  • Plant Biology Part 1 and Part 2 - You'll need to know the different parts of a plant, as well as what each part's function is. You'll also need to be able to identify the parts in a picture. The first site has a good overview of the different parts of the plant, click on each get a brief description. It also has a quiz. The second site is more of a read but goes into more detail.
  • How Roots Work - A very simple explanation of how the roots of a plant draw the water and nutrients from the surrounding soil.
  • Overview of Photosynthesis - Understand the process as well as the chemical equation. Don't get upset that this is a site for kids. It has a lot of good information in it. You wouldn't believe how hard it is to find a decent illustration of the process of photosynthesis. The best one I've found can be seen here.
  • Alternation of Generations - The most basic explanation I've found. A more in-depth explanation can be found on the Wikipedia entry for this topic.
  • Plant Reproduction - A lot of information here, but you need a firm understanding of the process for the Biology CLEP. There's eight pages of information here; so you'll need to go through them at your own speed. Know Meiosis, Diploid, Haploid, Gametes, Mitosis, and pretty much every other underlined word on these pages, just follow the links.
  • Plant structure and growth - Builds off the before mentioned material, but is in a quiz format. You probably won't know this at first, so answer what you do know and study the rest. Has the best diagrams for this that I've seen.
  • Plant Hormones and Transport - You will probably be asked to identify which hormone has the stated effect. My advice would be to read this entire page. While some of it will be covering material already seen in the above topics, it goes into more detail regarding nutrient transfer than any other source I've seen. Know this material!
  • Photoperiodism and Tropism - A great overview of these two topics. If you scroll upwards, there is another section describing plant hormones that I didn't include above due to lack of space.

Animal-Related Material (With an emphasis on vertebrates)

Molecular and Cellular Biology (33% of the exam)

Chemical Composition of Organisms

  • Chemical Bonds and Reactions - Obviously understand what each is, but also understand the sub groups (Ionic Bonds and Covalent Bonds)
  • Water and its properties - Just start at the top and work your way down.
  • Biomolecules - Know what each of the below are, and how organisms use them.
  • Origin of Life - Philosophical debates aside, know the Big Bang Theory as well as the different accepted periods of life on earth. Also of note is the bottom portion talking about Microscopes. The Biology CLEP may quiz you on the different units of measurement as well as the types of microscopes, so you may as well learn this now.


  • Cell Organelles - Subunit of cells with specialized purpose. Atoms are organized into molecules. Molecules are organized into organelles. Organelles are organized into cells......
  • Cell Membranes - Know the purpose as well as the makeup.
  • Prokaryotic Cells - Organisms whose cells do not contain a Nucleus.
  • Eukaryotic Cells - Organisms whose cells contain a Nucleus. Most living organisms fall under this category (including humans).


  • Enzyme-substrate complex - Because I like pictures with my explanations.
  • Coenzymes - A cofactor that is loosely bound to a protein
  • Inorganic Cofactors - Typically metal ions
  • Regulation and Inhibition - Included the definition of the process as well as how it's done. I'd know both of them for the Biology CLEP. You don't need to get too far into the weeds, but at least understand the basics.

Energy Transformations

Cell Division

  • Chromosome Structure - Interesting in its own right, but make sure you know the basic structure along with the different stages below.
  • Meiosis and Mitosis - Best explanation I've seen for this.
  • Cytokinesis - Know what it is, and know what the exception is.

Chemical Nature of the Gene

  • Watson-Crick Model - A good overview. Try this link for the background story. It's a fascinating one to read.
  • DNA Replication - A good overview of the process as well.
  • Mutation - Know the different types of mutations. To be safe I would check out the previous page as well on Chromosome mutations. A bit of extra knowledge won't hurt. Check out this resource as well for some more depth and causes of mutation. No need to go too deep on that one.
  • Control of Protein Synthesis - A great overview that touches on the below topics as well.
    • Transcription - A good explanation of the process.
    • Translation - If you kept reading on the above link, you've likely already seen this. If not, then read it here and know it well!
    • Posttranscriptional Processing - This was probably the easiest portion of this entire section for me to grasp.
  • Structural and Regulatory Genes - I wish I could find something for you a bit more detailed on Regulator Genes, though it's pretty straightforward concept. Just know what both of these are and what they do.
  • Transformations
  • Viruses - Spend some time on this one. Understand what they are, how they spread and how they are treated. Understand what vaccines are as well (Dead or weakened forms of the virus). Another great source with pics!

Population Biology (33% of the exam)

Principles of Ecology

  • Energy Flow and productivity in ecosystems - I usually try not to dip too deeply into Wikipedia sources, but they really nail Ecology so expect to see more of it.
  • Biogeochemical Cycles - An absolutely great explanation. There's a grad student somewhere who should be proud of themselves for their work on Wikipedia's Ecology series.
  • Population Growth Rate - It's not listed on the CollegeBoard site, but you'll need to know this formula. Even if it doesn't show up on the Biology CLEP, it will show up on the World Population Excelsior exam and I think I remember seeing it on the Sociology CLEP as well. You may as well learn it now. Besides, it may win you some money on Jeopardy one day. ;)
  • Population Growth and Regulation - Pretty self explanatory. Just know what it is and what phases a population normally goes through and why.
  • Community structure, growth, and regulation - Everything you'll need to know about ecological communities.
  • Habitat (Biotic and Abiotic Factor)
  • Concept of Niche - A simple concept that isn't so simple. Know what makes up an organism's niche.
  • Island Biogeography - I can attest to this having lived on both Hawaii and Cuba. Islands = nature on crack. Know the influencing factors.
  • Evolutionary Ecology
    • Life History Strategies - Different name, but the same concept. Another great article on this is found here. Towards the bottom of this article it explains how sharks are similar to humans in their Life History Strategy. Helped me understand this better.
    • Altruism
    • Kin Selection

Principles of Evolution

Principles of Behavior

Social Biology

  • Human Population Growth - Remember this page? I knew I remembered that formula from the Biology CLEP! Read the whole page this time, not just the formula.
  • Human intervention in the natural world - The gist of this section is - "Humans are wrecking the planet!" Using up resources, destroying the natural order of things, etc. You may get one or two questions asking about humanity's impact on the natural order, which is almost always a bad thing.
  • Biomedical Progress - Know about contraception and birth control, but also know the "very" basics of genetic engineering. (I don't remember being asked about this one on the exam, but it's on CollegeBoard's list so here it is)

Recommended bargain-priced study resources

Always check your library first! You may be able to find some of these for free. You don't have to buy the officially recommended resources all the time. If you're the type of person that prefers to study from a textbook source however, then please see below.

CLEP Biology (REA) with CD-ROM - The Best Test Prep for the CLEP Exam: with REA's TESTware (Test Preps) - Be careful with this one. Like a moron, I took my first Biology CLEP cold, so I was able to use this book after the fact and compare how much it covered. To be fair, there's entirely too much information in the Biology CLEP to study it with anything less than a textbook, but I was still somewhat dissapointed with the REA offering. Don't use this on it's own. I'd use it with a textbook, InstantCert, or the AP book to feel confident about passing the Biology CLEP.

CliffsAP Biology (Cliffs Ap Biology) - It's for the Biology AP exam, but I've always enjoyed using AP books to study for CLEP's.

One of the things that this book has that the CLEP counterparts don't are the lab questions. You may have noticed earlier when I mentioned you'll want to learn the different types of microscopes and measurements when using them. Though measurements and lab questions aren't listed on CollegeBoard's website, I did get some questions concerning them on my Biology CLEP. The AP book covers the lab quetsions well.

If you don't know what InstantCert is, then click here for the scoop as well as a discount code: **InstantCert Academy**

InstantCert Academy - Biology Exam Specific Feedback - Six pages of in-depth study resources and after-action reports. My advice is the same for the six credit exams - I highly suggest Instant Cert. The ability to see exactly what many people were quizzed on helps when studying for these broad general study CLEP's.

Be sure to check out the InstantCert Flashcards for the Biology CLEP as well. There are almost 900 of them for Biology alone, and they will help you pass.

Closing Thoughts

Six... freaking..... days of building this study guide. I'm confident I could walk in and take the Biology CLEP right now with little problems after all the re-studying and research I've done preparing this study guide. The upside is I can feel pretty confident about your ability to pass the Biology CLEP if you use the above resources.

Please study for this one. Don't be like me and try to take it cold. It wasn't one of my smarter moves.

I followed the CollegeBoard areas of study pretty closely, but I did put in a few things here and there that they didn't cover. One thing I would highly suggest is to pick up the AP book from above and go over the lab portions. Those will help you out if you end up getting hit with the same version of the CLEP that I took.

This one's worth six credits, so it's worth putting in the time and effort to earn them. You can do it!

Best of luck!

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