Chemistry of Life
Free
Cram sheet for water, biomolecules, and the questions that show up early in the year.
AP Biology
High-yield notes for the night before the unit test.
Short AP Bio PDFs: what the exam weights, the traps students miss, and practice with explanations. Original notes. Checkout is on Gumroad — pay once, keep the file.
Instant PDF Gumroad handles payment. The file lands in your email.
Original notes Written for exam structure — not copied from a textbook.
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Guides
Cram guides are $12. Practice packs are $9. Complete packs bundle both for $15.
Cell Structure
$12 cram · $9 practice
Membranes, organelles, SA:V, tonicity, and water potential.
Cellular Energetics
$12 · $9 · $15 pack
Enzymes, photosynthesis, and cellular respiration — the unit that eats the most study time.
Cell Communication
$12 cram · $9 practice
Signaling, feedback, mitosis, and checkpoints.
Heredity
$12 cram · $9 practice
Meiosis, Mendel, linkage, and non-Mendelian inheritance.
Gene Expression
$12 · $9 · $15 pack
Transcription, translation, operons, and regulation. Includes a complete pack.
Natural Selection
$12 · $9 · $15 pack
Hardy–Weinberg, speciation, and phylogeny. Highest-weighted unit on the exam.
Ecology
$12 cram · $9 practice
Energy flow, nutrient cycles, populations, and communities.
Free notes
Short pages you can use without buying anything.
Hardy–Weinberg in 3 steps
Start from the recessive phenotype. Find q, then 2pq. Chi-square cutoff 3.84.
Lac operon: high vs low vs off
Track the repressor and CAP. Do not write “the operon turns on.”
Water potential in 3 lines
Ψ = Ψs + Ψp. Solute makes Ψs negative. Water goes to lower Ψ.
Meiosis vs mitosis
Homologs in meiosis I. Sisters in meiosis II. Crossing over is prophase I.
Energy flows. Matter cycles.
NPP = GPP − plant respiration. About 10% moves up a trophic level.