What the TEAS Science Section Actually Tests
The TEAS science section covers biology, chemistry, anatomy and physiology, and reading/scientific reasoning. It is 50-65 questions depending on which version of the test you take, and you have about 60 minutes. Most people underprepare for the chemistry portion. They focus on biology because it feels familiar, and then they walk into the exam cold on stoichiometry and the periodic table. I spent a week grading practice exams for students applying to associate nursing programs. The pattern was consistent. People who scored in the 75th percentile or above had two things in common. They had done every practice problem twice, and they kept a error log that tracked exactly why they missed each question. The rest just took practice tests and moved on without reviewing their wrong answers. That is not how you improve from a 55 to an 80 on this exam.
Where to Find Teas Practice Questions Science
The ATI website sells official practice tests and the Study Guide. Those are the closest thing to the real exam in terms of format and difficulty. You can also find free questions on sites like Quizlet, but the quality varies wildly. Some of the free sets have answers that are flat out wrong. I once saw a question about mitosis where the answer key said cytokinesis happens before prophase. That kind of error shows up more often than you would expect on user-generated content. There are also commercial prep books from Kaplan and other publishers. They are fine for content review, but their practice questions tend to be easier than the actual TEAS. The real exam throws curveballs like integrated reading passages with data tables in the science section. Most third-party materials do not replicate that format well.
How to Use Practice Questions Without Wasting Time
Here is the system that actually works, and it is not complicated. Take a full practice test under timed conditions. Grade it honestly. Then go through every single wrong answer and write down three things: what the question was testing, why you chose the wrong answer, and what the right reasoning is. This usually takes 45 to 90 minutes for one test. It feels slow. It is not. This step alone improves scores more than doing three additional practice tests without review. I remember one student who kept missing questions about the nephron. She would guess the right answer sometimes by memorizing diagrams, but she did not understand the flow of filtrate through the structures. So she kept getting tripped up when the question changed the wording. We spent one session going through a blank nephron diagram and tracing blood flow, filtrate movement, and reabsorption step by step. After that, she stopped missing those questions entirely. The practice questions were not the problem. The gap in her understanding was.
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Biology: What to Focus On
Cell structure and function is the biggest chunk. You need to know the difference between osmosis, diffusion, and active transport. You need to understand mitosis and meiosis well enough to answer questions about chromosome numbers in daughter cells. A lot of people lose points here on questions like "How many chromosomes does each daughter cell have after meiosis if the parent cell has 46?" The answer is 23, but students who are half-prepared will pick 46 because they confuse the two types of cell division. Genetics is another area that shows up more than people expect. Punnett squares, dominant and recessive traits, blood type inheritance. Know how to read a pedigree chart. These questions are usually straightforward if you have practiced them, but they eat time if you are figuring it out for the first time during the exam. The human body systems section covers all eight major systems. You do not need to memorize every bone in the hand. You do need to know what the large intestine does, where gas exchange happens, and how the renal system maintains homeostasis. The exam loves questions about negative feedback loops. Body temperature regulation and blood glucose control come up regularly.
Chemistry: The Part Everyone Skips
This is where most nursing applicants struggle. The TEAS chemistry section covers atomic structure, the periodic table, chemical bonding, chemical reactions, equations, and basic organic chemistry. You need to know how to balance simple equations. You need to understand pH and the difference between acids and bases. Molarity calculations show up occasionally, so know the formula. I had a student who skipped chemistry practice entirely for three weeks before her test date. She ended up with a 35th percentile score in that section. She could do biology fine, but the chemistry dragged her overall score down enough to miss the cutoff for her program. Two weeks of daily chemistry review brought her to the 60th percentile. It is not that chemistry is hard. It is that most people start preparing for it too late.
Reading and Scientific Reasoning
The TEAS includes a reading component that is tied to scientific passages. You will get passages with graphs, charts, and tables. You need to interpret data, identify hypotheses, and understand experimental design. These questions test your ability to think like a scientist, not just recall facts. Practice with passages that include visual data. Look at graphs and figure out what the independent and dependent variables are. Learn to spot controlled variables. If a passage describes an experiment and asks what would invalidate the results, the answer usually involves a confounding variable that was not controlled. This is a pattern you can learn if you see enough examples.
Common Mistakes That Tank Scores
Running out of time is the number one issue. The science section moves fast. If you spend two minutes on a single question, you will not finish. Learn to flag questions you are unsure about and move on. You can come back to them if you have time. Second, overthinking answers. The TEAS does not reward cleverness. It rewards knowledge. If you second-guess yourself and change a correct answer to an incorrect one, that happens a lot. Stick with your first instinct unless you have a clear reason to change it. Third, ignoring weak areas. Taking practice tests and never reviewing the questions you got wrong is the fastest way to stay stuck at the same percentile. Track your performance by topic. If you are scoring below 60 percent on chemistry, spend proportionally more time on chemistry. The test does not care that you find biology more interesting.
What a Realistic Study Plan Looks Like
If you have four weeks before your test date, here is what I would suggest. Week one: content review for biology and anatomy. Do practice questions after each topic. Week two: chemistry review and practice. This is the section that needs the most attention. Week three: reading and scientific reasoning practice. Do at least two full practice tests this week under timed conditions. Week four: targeted review of your weak areas based on your error logs. Take one more full practice test near the end of the week. This is not a perfect system. It assumes you have some baseline knowledge coming in. If you are starting from zero in chemistry, you will need more time. But the principle is the same. Practice questions are only useful if you review them systematically. The mistake log is the tool that makes the difference between guessing your way through and actually improving.
