AP Biology 7-Day Cram Plan

title: "AP Biology 7-Day Cram Plan" description: "A structured week-long AP Biology study plan: daily deep dives into all 8 CED units, FRQ practice, formula sheet mastery, and full-length mocks. Score a 5 in 7 days." date: "2026-01-15" examDate: "May AP Exam" topics:

• Chemistry of Life
• Cell Structure and Function
• Cellular Energetics
• Cell Communication and Cell Cycle
• Heredity
• Gene Expression and Regulation
• Natural Selection and Evolution
• Ecology

You have seven days until the AP Biology exam. This schedule is designed to cycle through all 8 CED units at varying intensity, hitting the highest-yield topics first, then spiraling back to reinforce weak areas. Adjust timing if you're already strong in a unit.

Each day: 3–4 hours focused study. Mix review with practice problems and FRQ setup.

Daily Study Schedule

| Day | Focus | Review (90 min) | Practice (2.5 hrs) | Key Deliverable | |---|---|---|---|---| | Monday | Chemistry of Life + Enzymes | Water, macromolecules, enzyme kinetics | 20 MC + enzyme graph interpretation | Enzyme inhibition types (competitive vs non-) locked | | Tuesday | Cell Structure & Transport | Organelles (especially mitochondria, chloroplast), membrane structure, active vs passive | 25 MC on transport + osmosis FRQ | Design an experiment on isotonic/hypertonic solutions | | Wednesday | Photosynthesis & Cellular Respiration | Light reactions (Z-scheme), Calvin cycle, glycolysis, Krebs, ETC, ATP yield | 30 MC + one data-analysis FRQ | Respirometer trace analysis fluent | | Thursday | Heredity & Genetics I | Mendelian patterns, Punnett squares, monohybrid/dihybrid, chi-square setup | 25 MC + one chi-square FRQ | Chi-square test ready for exam | | Friday | Heredity & Genetics II + Hardy-Weinberg | $p^2 + 2pq + q^2 = 1$, allele frequencies, population genetics, speciation | 25 MC on HW + full-length genetics FRQ | Allele frequency calculations automatic | | Saturday | Cell Communication, Cell Cycle, Mitosis/Meiosis | G-protein signaling, receptor cascades, mitotic phases, meiosis I vs II, nondisjunction | 30 MC + signal transduction FRQ | Draw and label both mitosis and meiosis in 10 min | | Sunday | Evolution & Ecology + Full Mock Exam | Natural selection evidence, population ecology, community interactions, energy pyramids | 15 MC + full 6-FRQ timed exam (2.5 hrs) | Score and identify weak FRQ patterns |

Monday: Chemistry of Life & Enzyme Basics (3.5 hrs)

Review (90 min)

• Water properties: hydrogen bonding, cohesion/adhesion, surface tension, heat capacity — why water is a universal solvent.
• Macromolecules: carbohydrates (monosaccharides, polysaccharides, glycosidic bonds), lipids (saturated vs unsaturated, phospholipid bilayer), proteins (amino acids, peptide bonds, quaternary structure), nucleic acids (deoxyribose vs ribose, phosphodiester backbone).
• Enzyme function: active site shape, substrate specificity, induced fit model, activation energy lowering ($E_a$).
• Enzyme kinetics graph: $V_{max}$ (plateau), $K_m$ (substrate concentration at half $V_{max}$).
• Enzyme inhibition: competitive (inhibitor mimics substrate, $K_m$ increases), non-competitive (allosteric, $V_{max}$ decreases).
• Factors affecting enzyme rate: pH, temperature, substrate concentration, cofactors, coenzymes (NAD⁺, FAD).

Practice (2.5 hrs)

• 20 mixed MC on macromolecules and enzyme kinetics.
• 1 FRQ: given an enzyme kinetics graph with and without inhibitor, identify the inhibitor type and explain why $V_{max}$ or $K_m$ changed.
• Sketch a Michaelis-Menten curve and label $V_{max}$ and $K_m$.

💡 Key insight: $K_m$ tells you substrate affinity; lower $K_m$ = higher affinity. $V_{max}$ tells you enzyme capacity. Competitive inhibitors look like substrate, so they fight for the active site — only a higher substrate concentration can overcome them.

Tuesday: Cell Structure & Transport (3.5 hrs)

Review (90 min)

• Prokaryotic vs eukaryotic: organelles, nucleus, size, complexity.
• Eukaryotic organelles: nucleus (DNA, RNA), mitochondria (cristae, matrix, ATP production), chloroplast (thylakoid, stroma, photosynthesis), rough ER (ribosomes, protein synthesis), smooth ER (lipid synthesis), Golgi (modification, packaging), lysosomes (hydrolytic enzymes, prokaryotes lack them), vacuoles (storage, turgor), cytoskeleton (microtubules, microfilaments).
• Membrane structure: fluid mosaic model, phospholipid bilayer, cholesterol, embedded proteins, carbohydrate chains.
• Passive transport: diffusion (simple, through lipid bilayer), osmosis (water follows solutes), facilitated diffusion (protein channel, no energy).
• Active transport: Na⁺/K⁺ pump, uses ATP, moves against concentration gradient.
• Bulk transport: endocytosis (phagocytosis, pinocytosis), exocytosis (vesicles fuse with membrane).

Practice (2.5 hrs)

• 25 MC on organelles and transport mechanisms.
• 1 FRQ: "Design an experiment to determine whether a substance enters a cell via passive or active transport. Identify the independent variable, dependent variable, control, and expected results."
• Identify which organelles are present in plant vs animal cells (e.g., chloroplast, large central vacuole in plants).

⚠️ Common trap: Osmosis is the movement of water, not the movement of solutes. If you're asked about salt moving across a membrane, that's active transport or facilitated diffusion, not osmosis.

Wednesday: Photosynthesis & Cellular Respiration (3.5 hrs)

Review (90 min)

• Photosynthesis structure: thylakoids (stacked = granum), stroma.
• Light reactions (thylakoid):
  • Photosystem II (P680): absorbs light, water photolysis ($2H_2O \to O_2 + 4H^+ + 4e^-$), electron transport chain to Photosystem I.
  • Photosystem I (P700): absorbs light, electrons enter, NADP⁺ → NADPH.
  • Chemiosmosis: $H^+$ gradient drives ATP synthesis.
  • Output: ATP, NADPH, O₂.
• Calvin cycle (stroma):
  • Carbon fixation: CO₂ + RuBP (5C) → 3-PG (3C), catalyzed by RuBisCO.
  • Reduction: 3-PG → G3P (uses ATP, NADPH).
  • Regeneration: G3P → RuBP (uses ATP).
  • For every 3 CO₂, one G3P exits (used for glucose synthesis).
• Cellular respiration:
  • Glycolysis (cytoplasm): glucose (6C) → 2 pyruvate (3C), 2 ATP net, 2 NADH.
  • Krebs cycle (mitochondrial matrix): acetyl-CoA (2C) enters, oxidation releases CO₂, 3 NADH, 1 FADH₂, 1 ATP per cycle.
  • Electron transport chain (cristae): NADH, FADH₂ → electrons, $H^+$ pumped, chemiosmosis drives ATP synthesis (~2.5 ATP per NADH, ~1.5 per FADH₂).
  • Total: ~30–32 ATP per glucose (theoretical max).

Practice (2.5 hrs)

• 30 MC: half on photosynthesis (light reactions, Calvin cycle, rate factors), half on respiration.
• 1 FRQ: "A leaf exposed to light at varying CO₂ concentrations shows different rates of photosynthesis (given graph). Explain which stage(s) of photosynthesis are affected at low vs high CO₂, and why."
• Sketch the light reactions with P680, P700, and label where NADPH and ATP are made.

🎯 Exam favorite: "Why does the Calvin cycle require ATP even though it's not the energy-releasing stage?" Answer: regeneration of RuBP consumes ATP; reduction also consumes ATP. The cycle is driving CO₂ fixation, which is thermodynamically unfavorable without energy input.

Thursday: Heredity I — Mendelian Genetics & Chi-Square (3.5 hrs)

Review (90 min)

• Terminology: homozygous, heterozygous, dominant, recessive, phenotype, genotype, allele.
• Monohybrid cross (one trait): Aa × Aa → 3:1 ratio (3 dominant phenotype : 1 recessive).
• Dihybrid cross (two traits): AaBb × AaBb → 9:3:3:1 ratio (9 A_B_ : 3 A_bb : 3 aaB_ : 1 aabb).
• Test cross: heterozygote × homozygous recessive → reveals gamete types.
• Pedigree analysis: dominant traits (affected person often has affected parent), recessive traits (can skip generations, two unaffected parents can have affected child), X-linked traits (males more often affected, carrier females).
• Chi-square test: $\chi^2 = \sum \frac{(O-E)^2}{E}$. Degrees of freedom = phenotypic classes − 1. Compare to critical value table (typically $\chi^2_{\text{crit}} \approx 3.84$ for 1 df, α = 0.05). If $\chi^2 > \chi^2_{\text{crit}}$, reject the hypothesis; data deviate significantly from expected.

Practice (2.5 hrs)

• 25 MC: Punnett squares, pedigrees, chi-square reasoning.
• 1 FRQ: "A fruit fly cross yields 120 wild-type flies, 40 mutant flies. Hypothesize the genotypes of the parents and test your hypothesis with a chi-square test. Show all work and conclude whether the data fit the expected ratio."

💡 Chi-square must-do: Set up a table with observed (O), expected (E), O−E, $(O-E)^2$, $(O-E)^2 / E$. Sum the last column. Show your critical value and conclusion.

Friday: Heredity II — Hardy-Weinberg & Population Genetics (3.5 hrs)

Review (90 min)

• Hardy-Weinberg equilibrium: $p^2 + 2pq + q^2 = 1$ (or $p + q = 1$).
  • $p$ = frequency of dominant allele.
  • $q$ = frequency of recessive allele.
  • $p^2$ = frequency of homozygous dominant genotype.
  • $2pq$ = frequency of heterozygous genotype.
  • $q^2$ = frequency of homozygous recessive genotype.
• Five assumptions: no mutation, no selection, large population (no genetic drift), no migration, random mating. Violation of any = evolution occurring.
• Using HW: calculate allele frequencies from phenotype data, predict next-generation genotype frequencies, test if population is in equilibrium.
• Non-Mendelian patterns: incomplete dominance ($A^R A^W$ = pink), codominance ($I^A I^B$ = both antigens), multiple alleles (ABO blood, MN blood), linked genes (crossover frequency reveals map distance), sex-linked traits.
• Speciation: reproductive isolation (behavioral, geographic, temporal, mechanical, gametic), allopatric (geographic barrier), peripatric (small founding group), sympatric (no barrier).

Practice (2.5 hrs)

• 25 MC: Hardy-Weinberg calculations, non-Mendelian patterns, speciation scenarios.
• 1 full FRQ: "In a population, 16% of individuals are homozygous recessive (aa). Calculate the allele frequencies and genotype frequencies. If the population meets Hardy-Weinberg assumptions, what will the frequencies be after 10 generations? If selection favors the heterozygote, how might allele frequencies change instead?"

⚠️ FRQ scoring trap: Simply stating "the population is NOT in Hardy-Weinberg equilibrium" earns minimal points. You must identify which assumption is violated (selection, mutation, migration, drift, or non-random mating) and explain the mechanism.

Saturday: Cell Communication, Cell Cycle, and Meiosis (4 hrs)

Review (90 min)

• Signal transduction:
  • Receptor types: G-protein-coupled (outside → G-protein → cAMP cascade), receptor tyrosine kinase (outside → autophosphorylation → protein cascade), ion channel (direct gate opening).
  • Second messengers: cAMP, IP₃, DAG, Ca²⁺.
  • Amplification: one signal molecule → many effector molecules.
  • Termination: phosphatase enzymes inactivate signaling proteins.
• Mitosis (somatic cell division, produces 2 identical diploid cells):
  • Prophase: nuclear envelope breaks down, spindle assembles, chromosomes condense, centrioles move to poles.
  • Metaphase: chromosomes align at cell equator (metaphase plate).
  • Anaphase: sister chromatids separate, move to opposite poles.
  • Telophase: nuclear envelope reforms, spindle disassembles.
  • Cytokinesis: cleavage furrow (animal) or cell plate (plant).
• Meiosis I (reduction, produces 2 haploid cells):
  • Prophase I: homologous chromosomes pair (bivalents), crossing over occurs, nuclear envelope breaks down.
  • Metaphase I: bivalents align at equator.
  • Anaphase I: homologous chromosomes separate (key: not sister chromatids).
  • Telophase I + Cytokinesis: two cells form, each with half the chromosomes.
• Meiosis II (like mitosis, sister chromatids separate):
  • Produces 4 haploid cells.
  • At the end, no two cells are identical (due to crossing over and random assortment).
• Errors: nondisjunction in meiosis I (both homologs go to one pole) or meiosis II (both sister chromatids go to one pole) → aneuploidy (trisomy, monosomy).

Practice (2.5 hrs)

• 30 MC: mitosis, meiosis, meiosis errors, signal transduction pathways.
• 1 FRQ: "A cell undergoes meiosis. Explain how crossing over and independent assortment each contribute to genetic variation in gametes. Then, describe what would happen if nondisjunction occurred during meiosis II."
• Draw and label all phases of mitosis and meiosis (practice on scratch paper).

🎯 Exam pattern: The exam loves asking "how many chromosomes in a daughter cell after anaphase I?" (Answer: haploid number, but each chromosome is still 2 sister chromatids until anaphase II.) Write "haploid with duplicated chromosomes" to earn full credit.

Sunday: Evolution, Ecology, and Full Mock Exam (4 hrs)

Review (60 min)

• Natural selection: evidence (fossil record, biogeography, comparative anatomy, molecular homology), mechanisms (stabilizing, directional, disruptive), adaptation vs microevolution vs macroevolution.
• Speciation: reproductive isolation barriers, allopatric vs sympatric, rate (gradualism vs punctuated equilibrium).
• Phylogenetics: phylogenetic trees, cladistics, molecular clock, outgroup, derived vs ancestral traits.
• Population ecology: exponential vs logistic growth, carrying capacity ($K$), density-dependent vs density-independent factors, life history strategies (r vs K selected).
• Community ecology: predation, competition, symbiosis (mutualism, commensalism, parasitism), succession (primary vs secondary).
• Ecosystem ecology: energy flow (10% rule), nutrient cycling (C, N, P), trophic levels, ecological pyramids (energy, biomass, numbers).
• Biodiversity: alpha vs beta vs gamma diversity, island biogeography, conservation strategies.

Practice (3 hrs 45 min)

• 15 MC on evolution and ecology.
• Full 6-FRQ timed practice exam (2 hours, strictly monitored):
  • FRQ 1 (8 pts, long): Data interpretation — given graph of allele frequency change over time in a population, identify selection pressure.
  • FRQ 2 (8 pts, long): Design experiment — propose an experiment to test a hypothesis about ecological interaction or population dynamics.
  • FRQ 3–4 (4 pts each, short): Conceptual questions on signal transduction, meiosis errors, or photosynthesis.
  • FRQ 5 (4 pts): Analyze a phylogenetic tree or energy pyramid.
  • FRQ 6 (4 pts): Calculate chi-square or Hardy-Weinberg from data.

After the exam:

Score it. Note which FRQ types you missed. If you scored < 70%, identify the lowest-scoring FRQ and redo it tomorrow morning before the real exam.

Post-Monday through Exam Day

Monday–Thursday: Review weak areas identified in the Sunday mock. Do 2–3 targeted FRQs per day focusing on your weakest patterns. Drill the formula sheet (chi-square, Hardy-Weinberg, water potential $\Psi = \Psi_P + \Psi_S$).

Friday (exam eve): Skim the last-minute checklist →. Sleep 8 hours.

Ready? Open the full AP Biology library → or jump to FRQ practice →.