MCAT practice, played as a game
Understand the science, then use it on test day.
2,488 original questions that explain why. Use that reasoning on passages and data, and a scheduler brings each one back before you forget it.
25 new questions a day and unlimited reviews, free. No account needed to start.
Answer to power your first organelle
Lysine has pKa values of 2.18, 8.95 and 10.53. Its pI is:
Pick an answer. A right one sends ATP into the cell.
Scroll into the nucleus.
Every figure in the Codex is drawn in code, so you can watch the mechanism move. Keep scrolling and this one replicates.
- 1Two strands, running opposite ways.A pairs with T through two hydrogen bonds, G with C through three.
- 2Helicase opens the fork.A ring of six subunits rides one strand and pries the helix apart, spending ATP as it goes.
- 3DNA polymerase builds 5′ to 3′.One strand is copied continuously toward the fork. The other is copied in fragments, away from it, each starting from a short RNA primer.
- 4Two copies, each half original.Every daughter helix keeps one parent strand and gains one new strand.
99 figures drawn in code. 94 chemical structures checked against PubChem.
It comes back before you forget it.
Set your test date. The scheduler spaces each question’s reviews so that every one lands before the exam. How fast you answer counts as the rating, so you never grade yourself.
The gaps grow while the memory holds: 2, 3, 9, 25, 28 days, then close up near test day.
Answered right every time: reviews on day 0, 2, 5, 14, 39, 67, 79, 85. Test day is day 90.
The first reviews of one card, worked out by the app’s own scheduler: FSRS-5, aiming for 92% recall.
Use it on passages and data. Sit a full-length. Drill CARS.
Full-length exam 230 questions, CARS 53 in 90 minutes
ATP Quest Full-Length 1
Four sections in exam order with breaks, scored with every explanation. Highlight, strike out and flag, the way you will on test day.
Scenario
A student titrates 50.0 mL of a 0.10 M aqueous weak base, B, with 0.10 M HCl at 25 °C. The pH is 9.0 when exactly half of the base has been neutralized.
Question
CARS practice 40 passages, 40 drills
Every wrong answer names its trap.
Full passages, timed or untimed, skill drills and a mistakes queue. Three passages and the strategy cards are free.
It can be inferred from the passage that the author believes the hourly wage:
A. came into general use before public clocks spread to market towns.
Trap: Flipped, the opposite
B. had no effect on the way labor was organized or supervised.
Trap: Overstated, too extreme
C. depended on a way of dividing time that the clock made available.
The answer
D. was resisted by laborers who were accustomed to payment by the task.
Trap: Never said, out of scope
“Everything I say is true. None of it is in the passage.”
2,488
original questions in 50 topics, each tagged to the AAMC’s content categories.
Bio/Biochem
995
24 topics
Chem/Phys
626
14 topics
Psych/Soc
840
11 topics
CARS skills
27
plus 40 full passages
Preview: the free organelles, built
Spend what you earn.
Right answers earn ATP. Spend it in the Foundry on organelles: each one makes ATP on its own, so the cell keeps working while you are away.
- RibosomeNext to build+6% ATP from every correct answer · 120 ATP
- MitochondrionAfter Ribosome level 2+14% passive ATP generation · 400 ATP
- Rough ERAfter Mitochondrion level 2Earn a hint every 4-answer combo · 900 ATP
- Golgi ApparatusPremiumCombo multiplier cap +0.5 · 2,200 ATP
ATP from this page. The first build is topped up to 120 ATP, once, as after a first quest.
You start as a Monomer. Your first 300 ATP makes you a Dimer.
Free every day. Premium when it counts.
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25 new questions a day across every topic, unlimited reviews, the scheduler, Rapid Fire.
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All of Premium for 90 days, paid once. Made for a single study block before test day.
Keep your cell.
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