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MCAT Flashcards: What to Memorize, What to Skip, and How to Use Them

by Hawar Palani in MedSchool Tips

Every MCAT student hits the same wall eventually. You understand glycolysis when you read about it, you follow the lens equation in the video, and then a week later the amino acid structures, the hormone list, and half of Psych/Soc have quietly leaked out of your head.

That's not a sign you're bad at this. It's just how memory works. Information you don't revisit fades, and the MCAT covers a lot of information.

Flashcards are the classic fix, but they can also turn into a time sink that eats hours you should be spending on practice passages. Here's how to use MCAT flashcards so they actually raise your score, and what to leave off your cards entirely.

Are MCAT Flashcards Worth It?

Yes, for the right material. Flashcards are one of the most efficient ways to lock in discrete, memorizable facts: amino acids, rate-limiting enzymes, hormones, physics equations and units, organic functional groups, and the large vocabulary of Psych/Soc. They are not a substitute for passage practice, because the MCAT mostly tests whether you can apply that knowledge to unfamiliar research scenarios.

The best approach for most students is a short daily review session you can realistically finish (often somewhere in the 30–60 minute range), with new cards capped so your reviews never snowball. Pair that with daily practice questions, and flashcards become the foundation that makes passages feel easier instead of a separate project competing for your time.

What Belongs on Your Flashcards, Section by Section

The rule of thumb: if you'd need to recall it instantly in the middle of a passage, and you can't reasonably derive it on the spot, it belongs on a card.

Bio/Biochem

  • The 20 amino acids: structure, one- and three-letter codes, and side-chain properties (nonpolar, polar, acidic, basic).
  • Rate-limiting enzymes: PFK-1 for glycolysis, fructose-1,6-bisphosphatase for gluconeogenesis, isocitrate dehydrogenase for the citric acid cycle, glycogen synthase and glycogen phosphorylase for glycogen metabolism, acetyl-CoA carboxylase for fatty acid synthesis, carnitine acyltransferase I for fatty acid oxidation, and HMG-CoA reductase for cholesterol synthesis.
  • Hormones: where each one is released, what it targets, and what it does. For example, ADH (made in the hypothalamus, released from the posterior pituitary) increases water reabsorption in the collecting duct; aldosterone from the adrenal cortex increases sodium reabsorption and potassium secretion.
  • Enzyme kinetics basics: how competitive, noncompetitive, and uncompetitive inhibitors change Km and Vmax.

Chem/Phys

  • Core equations with units: kinematics, work and energy, Ohm's law, the thin lens equation, Bernoulli's equation, and the ideal gas law. Put the units on the card, since unit analysis is one of the fastest ways to check an answer.
  • Sign conventions: for lenses and mirrors, thermodynamics (heat and work), and electrochemistry.
  • Organic chemistry: functional groups, common reaction types, and which reagents do what.
  • Key relationships: for example, that a lower pKa means a stronger acid, or that resistors in parallel always have a lower combined resistance than the smallest individual resistor.

Psych/Soc

This is where flashcards shine the most. Psych/Soc rewards precise definitions, and many terms sound alike. Make cards for developmental theories (Piaget, Erikson, Kohlberg), memory and learning concepts, cognitive biases and attribution errors, sociological theories, and research design terms. Add a short example to each card, since the exam will describe a scenario rather than name the concept for you.

CARS

Skip flashcards here almost entirely. CARS doesn't test outside knowledge, so your time is much better spent on timed passage practice and reviewing your reasoning on every miss.

What to Leave Off Your Cards

Bad cards waste more time than no cards. Leave these out:

  • Paragraph-length answers. If the back of a card takes 30 seconds to read, split it into several smaller cards or drop it.
  • Things you can derive. If you understand where a relationship comes from, you don't need to memorize it separately. Make one card for the underlying principle instead.
  • Ultra-obscure details. A card for every footnote in your content book inflates your daily reviews without moving your score.
  • Reasoning skills. Interpreting experiments, reading graphs, and evaluating arguments are built through practice passages, not cards.

Anki vs. Physical vs. Premade Decks

There's no single right format. The best deck is the one you'll actually review every day.

Anki and Digital Cards

Anki uses spaced repetition to schedule each card right before you're likely to forget it, which makes it very efficient for large amounts of material. The trade-off is that it's easy to add too many cards, and missing even a few days can create a pile of overdue reviews that feels impossible to clear.

Physical and Illustrated Cards

Physical cards get you away from screens, work well for quick sessions between classes, and pair naturally with visual memory, especially when cards include diagrams of structures and pathways. Without an algorithm, you'll need a simple system, like sorting cards into "know it," "shaky," and "don't know" piles and reviewing the shaky piles more often.

Make Your Own or Use Premade?

Making your own cards helps you process the material, but it takes a lot of time. Premade decks save that time and make sure the core content is covered. Many students do best with a hybrid: a premade deck for core content, plus their own cards for concepts they keep missing in practice questions.

How to Use Flashcards Without Letting Them Take Over

  1. Start during content review. Add cards as you finish each topic so retention builds as you go, instead of facing a mountain of cards in your final weeks.
  2. Cap your new cards. Pick a daily limit that keeps your total review time manageable, and adjust down if reviews start creeping up.
  3. Review every day. Consistency matters more than volume. A short daily session beats a marathon on the weekend.
  4. Recall before you flip. Say the answer out loud or write it down before looking. If you just recognize the answer after flipping, mark it as wrong.
  5. Turn practice misses into cards. When you miss a question because of a fact you forgot, make a card for it. These are some of the highest-value cards you'll ever make.
  6. Shift your balance as test day gets closer. In your final weeks, keep up with reviews but put most of your energy into full-length exams and passage review. For more on building your resource plan, see our guide to the best MCAT study resources.

What Most Students Get Wrong About MCAT Flashcards

The most common mistake is treating flashcards as the whole plan. Knowing every fact on a deck won't help much if you haven't practiced applying that knowledge to dense experimental passages under time pressure. Cards support practice; they don't replace it.

The second mistake is confusing recognition with recall. Flipping a card and thinking "oh right, I knew that" is not the same as producing the answer yourself. Be honest when you grade your cards, or the spacing algorithm (or your pile system) will stop working.

The third mistake is making cards for everything. A 10,000-card deck sounds impressive, but if reviews take three hours a day, something else in your prep is going to suffer. Fewer, better cards almost always win.

A Deck That's Ready When You Are

If you'd rather spend your time reviewing than building a deck from scratch, the MCAT Flashcard Set from MedSchoolBro gives you 477 illustrated cards built for fast, visual review, so structures, pathways, and key concepts are easier to recall when a passage needs them. If you review digitally in Anki, the Anki Clicker from MedSchoolBro lets you flip and grade cards with a handheld clicker instead of sitting at your keyboard, which makes daily sessions easier to stick with.

 

Frequently Asked Questions

Are flashcards enough to prepare for the MCAT? No. Flashcards are great for memorizing discrete facts, but the MCAT mostly tests how you apply knowledge to passages and experiments. Use cards alongside daily practice questions and full-length exams, not instead of them.

How many flashcards should I review per day for the MCAT? There's no universal number. Aim for a daily review load you can finish consistently, often somewhere in the 30–60 minute range, and limit new cards so reviews don't pile up. If you regularly can't finish your reviews, reduce your daily new cards.

Should I use Anki or physical flashcards? Either can work. Anki schedules reviews automatically with spaced repetition, while physical cards are easier to use away from screens and work well for visual learners. The best choice is the format you'll use every day.

Do I need flashcards for CARS? Generally, no. CARS doesn't test outside content knowledge, so timed passage practice and careful review of your reasoning are a much better use of your time.

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That activation makes sense: lots of acetyl-CoA means plenty of fatty acid breakdown, so the cell has energy to spare and can afford to make glucose. Second, phosphoenolpyruvate carboxykinase (PEPCK) decarboxylates and phosphorylates oxaloacetate to form PEP, using GTP. Since oxaloacetate can't cross the inner mitochondrial membrane directly, it's usually reduced to malate, shipped to the cytosol, and oxidized back to oxaloacetate. That trip also generates cytosolic NADH, which the pathway needs later at the glyceraldehyde-3-phosphate dehydrogenase step. Bypass 2: Fructose-1,6-Bisphosphate to Fructose-6-Phosphate Fructose-1,6-bisphosphatase removes a phosphate in the cytosol, bypassing PFK-1. This is the key regulated step of gluconeogenesis, mirroring PFK-1's role as the key regulated step of glycolysis. It's inhibited by AMP (low energy, so don't spend ATP making glucose) and by fructose-2,6-bisphosphate. Bypass 3: Glucose-6-Phosphate to Glucose Glucose-6-phosphatase sits in the endoplasmic reticulum and removes the final phosphate so free glucose can leave the cell. It's present in the liver and kidney but absent in skeletal muscle, which is why muscle can't release glucose into the blood even from its own glycogen. A deficiency causes von Gierke disease (glycogen storage disease type I), with severe fasting hypoglycemia and lactic acidosis, a nice example of the MCAT linking enzymes to physiology. The Energy Cost Making one glucose from two pyruvate costs 4 ATP, 2 GTP, and 2 NADH. Compare that to the net 2 ATP glycolysis produces, and you can see why gluconeogenesis is tightly controlled. Running both pathways at full speed at the same time would just burn ATP for nothing (a futile cycle). Where Gluconeogenesis Happens Tissues The liver does most of the work. The kidney cortex contributes as well, and its share grows during prolonged fasting. Skeletal muscle and the brain don't supply glucose to the blood through gluconeogenesis. The brain and red blood cells are the main consumers that this whole pathway exists to protect. Compartments Gluconeogenesis spans three cellular locations, which the MCAT likes to test directly: pyruvate carboxylase in the mitochondria, most of the pathway in the cytosol, and glucose-6-phosphatase in the ER. If an answer choice says gluconeogenesis happens "entirely in the cytosol," it's wrong. Timing During Fasting Right after a meal, insulin is high and gluconeogenesis is low. In the hours after a meal and overnight, liver glycogen breakdown supplies much of the blood glucose while gluconeogenesis ramps up. Once liver glycogen is largely depleted, roughly a day into a fast, gluconeogenesis becomes the main source of new glucose. In prolonged starvation, the brain shifts toward ketone bodies, which reduces how much glucose the body has to make and spares muscle protein. 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PKA does two important things: it lowers fructose-2,6-bisphosphate levels by phosphorylating the bifunctional enzyme PFK-2/FBPase-2, and it inactivates liver pyruvate kinase. Both changes favor gluconeogenesis over glycolysis. Cortisol increases transcription of gluconeogenic enzymes like PEPCK and mobilizes amino acids from muscle. Insulin does the opposite on every front. Fructose-2,6-Bisphosphate: The Switch Fructose-2,6-bisphosphate activates PFK-1 and inhibits fructose-1,6-bisphosphatase. High levels (fed state, insulin) push the liver toward glycolysis. Low levels (fasting, glucagon) push it toward gluconeogenesis. If you understand this one molecule, you understand reciprocal regulation. Allosteric Signals Acetyl-CoA activates pyruvate carboxylase and inhibits pyruvate dehydrogenase, steering pyruvate toward glucose instead of the TCA cycle. AMP inhibits fructose-1,6-bisphosphatase while activating PFK-1. The logic is always the same: low energy favors glycolysis, high energy and low blood glucose favor gluconeogenesis. What Most Students Get Wrong About Gluconeogenesis The biggest mistake is treating it as glycolysis in reverse and stopping there. Gluconeogenesis MCAT questions rarely ask about the shared reversible steps. They ask about the bypass enzymes, where they are, and what controls them. The second mistake is the fatty acid trap. Students know fat is stored energy, so they assume it can become glucose. Even-chain fatty acids can't make net glucose, but glycerol and odd-chain fatty acids can. Expect answer choices built around that exact distinction. The third mistake is forgetting tissue differences. Muscle lacks glucose-6-phosphatase, so it can't export glucose. The liver can. When a passage mentions a muscle-specific enzyme deficiency versus a liver one, that difference usually decides the answer. A related classic: heavy alcohol use raises the NADH/NAD+ ratio, which pushes pyruvate toward lactate and oxaloacetate toward malate, starving gluconeogenesis and causing hypoglycemia. Making Metabolic Pathways Stick Gluconeogenesis is a pathway you need to recall fast and apply under pressure, which is exactly where visual, repeated review pays off. The MCAT Flashcard Set from MedSchoolBro gives you 477 illustrated cards, so enzymes, regulators, and pathway connections become pictures you can recall instead of lists you reread. When you're ready to test that recall in passage format, the MCAT Question Bank from MedSchoolBro has 3,000+ AAMC-style questions to practice applying metabolism under real test conditions.   Frequently Asked Questions What is the rate-limiting enzyme of gluconeogenesis? Fructose-1,6-bisphosphatase is generally taught as the key regulated (rate-limiting) step. It's inhibited by AMP and fructose-2,6-bisphosphate, and it mirrors PFK-1 in glycolysis. Pyruvate carboxylase is also heavily regulated, mainly through activation by acetyl-CoA. Can fatty acids be converted into glucose? Not even-chain fatty acids, because their acetyl-CoA can't be converted back to pyruvate and gives no net oxaloacetate in the TCA cycle. Odd-chain fatty acids can contribute through propionyl-CoA, and the glycerol from triglycerides is a genuine gluconeogenic substrate. On the MCAT, "fat can't become glucose" really means even-chain fatty acids. Why can't muscle perform gluconeogenesis to raise blood glucose? Muscle lacks glucose-6-phosphatase, so it can't remove the final phosphate and release free glucose into the blood. Instead, muscle sends lactate and alanine to the liver, which does the gluconeogenesis. That's the whole point of the Cori and glucose-alanine cycles. How does gluconeogenesis connect to glycogen metabolism? Both maintain blood glucose during fasting and are activated by glucagon. Glycogen breakdown handles the early hours, and gluconeogenesis takes over as liver glycogen runs low. Gluconeogenesis MCAT questions often ask which source dominates at a given point in a fast, so know the general timeline.

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