Learn Fifty-six original lessons implement all six cellular and molecular biology modules plus two course-wide synthesis destinations. Retained investigation and mixed-assessment work supports an explicit project defense; authored coverage is not certified practical participation or independent mastery.
This is the course outline. Open a unit to choose a lesson; every lesson opens on its own page. Explanations and experiments live inside those lesson pages.
Preparation: High-school biology and chemistry, ratios, graph slopes and basic algebra. Logarithms are introduced through a supplied buffer equation; no programming, calculus or physical chemical handling is required.
Course outcome: Defend a cellular mechanism across scientific evidence, chemistry, compartments, metabolism, signaling, inheritance and gene expression; discriminate measurement and sampling alternatives using quantitative inventories and falsifying predictions.
All lessons are directly accessible. Reused foundation explanations are identified where relevant; completing a different course does not award this course's evidence. The 56 registered lessons keep separate predictions, captures, practice responses and reflections.
Construct controlled causal contrasts, distinguish primary connectivity from conformation, audit biological material and buffer inventories, and test calibration predictions against independent standards.
Compare inhibition40% with artifact0 and20 units. Then change inhibition to0 while retaining the artifact. Record all four readings, not just the result that agrees with your prediction. Explain why a cell-free standard and a bypass answer different questions.
Set treatment effect0 and batch shift4. Compare the paired estimate with the confounded estimate. Then change the treatment effect while holding batch offset fixed. State the number of biological units and name a violation that pairing cannot remove.
Compare two four-residue chains with one eight-residue chain. Reconstruct input and output hydrogen and oxygen counts. Explain why identical total glucose input does not imply identical numbers of ends or released water molecules.
Compare pH7 at total4 and8mmol/L, keeping the challenge fixed. Then use pH6 with the smaller total and identify the model boundary. Record invalid approximations as invalid, not as missing evidence to hide.
Hold hydrolysis at0 and switch the conformation indicator. Then hold the indicator fixed and compare0,2 and5 cleavages. Keep a separate column for quantities the model does not predict, including activity and aggregation.
Compare q=0 and0.05 at the same intercept. Record fitted coefficients and both withheld residuals. Then change only the intercept and predict which quantities should remain unchanged. Explain why withholding standards makes a stronger range check than examining fitted points alone.
Keep signal0.6AU and compare artifact0,0.1 and0.15AU. Identify which displayed bounds remain unchanged and why. Then change the signal while retaining the same artifact; explain the difference between absolute artifact and relative concentration error.
Calibrate image evidence, distinguish cellular architecture and compartment roles, conserve finite inventories and audit membrane transport mechanisms against pressure, energy and measurement alternatives.
Compare(100,60) with(200,100) within the controls and compute each ratio explicitly. Then choose a supported pair of uniformly scaled recipes such as(40,20) and(80,40). Retain the schematic provenance and a source of real-image uncertainty that is absent here.
Hold feature separation200nm and vary enlargement from1 to4. Then hold enlargement fixed and change separation to400nm. Compare ratios, not merely the apparent distance on a large display.
Compare radius4/folding1, radius8/folding1 and radius8/folding2. Retain separate area, volume and ratio values. Name one biological transport variable that the geometric comparison leaves uncontrolled.
Compare outside8 atP1 andP2. At several displayed times reconstruct inside amount plus outside amount. Then set outside below2 to reverse the initial flux. Explain the difference between concentration and amount at equilibrium.
At outside100mmol/L, compare inside pressure0,0.2 and0.3MPa. Calculate both total potentials before reading the direction. State why the calculation does not supply final cell volume.
Compare competitor0 and2 across substrate1,4 and10. Locate half-maximal uptake and distinguish a changingKm from a changingVmax. Propose an assay control that could separate transport saturation from detector saturation. As a separate composition prediction, compare otherwise matched saturated-tail and cis-unsaturated-tail membranes during cooling: which should retain more fluidity? Would that alone establish a faster carrier rate?
Compare ratio11 and21 at drive20 and30kJ/mol cycles. Locate a case where the specified drive is insufficient. Explain why adding an ionic charge would require an additional electrical contribution rather than reuse of the same neutral ledger.
Hold true enrichment4 and vary contamination0,20 and50%. Record both marker signals and target enrichment. Explain why a target-enriched fraction is not itself proof of direct target–marker binding or of complete organelle recovery.
Hold pump4 and compare additional leak1 and3. Verify that outward leak equals the supplied inward pump in both states, while pH differences differ. Explain why balanced fluxes do not imply thermodynamic equilibrium.
Discriminate enzyme-rate mechanisms, audit free-energy coupling and reconstruct carbon, electron, proton and ATP inventories across respiratory and photosynthetic pathways.
Compare enzyme factors 1 and 2 using windows 0.1 and 2 min. Calculate the initial slope and endpoint average separately. Record substrate depletion and explain why an apparent failure of proportionality need not prove enzyme inhibition.
Compare inhibitor 0 and 2 at substrate 1, 4 and 10. Before reading the curves, predict whether increasing substrate can recover the reference capacity in each model. Identify one nonkinetic control that would challenge the interpretation.
Hold 45°C and compare exposure 0, 4 and 10 min. Then compare a cooler condition at the same exposure duration. Keep catalytic factor and active fraction in separate columns instead of treating observed rate as a single-mechanism measurement.
Compare Q=1 and 11 with driving magnitudes 25 and 35. Identify a condition where the coupled direction is favorable and one where it is not. Name the evidence needed to establish actual coupling rather than only an arithmetically favorable sum.
Compare glucose amounts 1 and 3 with demand 4. Keep investment, gross formation, net pathway yield and remaining demand balance separate. Explain why oxygen absence does not directly cancel glycolysis but can affect the wider carrier-regeneration context.
Compare oxidative entry fractions 0, 50 and 100% at two µmol glucose. Keep entry CO2 separate from cycle CO2, and verify total carbon including unentered pyruvate. State what extra information an isotope-origin claim would need.
Compare donor 4, 8 and 10 with oxygen 3. Then hold donor 8 and change oxygen from 0 to 4. Record both unused inventories and explain why an oxygen-limited endpoint does not determine the respiratory rate before that endpoint.
Compare ΔpH 0 and 1 at voltages 50 and 150 mV. Keep electrical and chemical contributions separate, then compare the four-proton budget with the stated ATP demand. Explain why the result is neither a rate prediction nor a universal proton/ATP ratio.
At glucose 2, compare lactate fractions 0, 50 and 100%. Reconstruct carbon, NADH regeneration and ATP separately. Explain why CO2 production is not a universal marker for every fermentation route.
Compare cyclic fractions 0 and 50% at 24 µmol photons. Keep linear/cyclic photon allocations, NADPH, O2 and the separately stipulated ATP contributions in a ledger. Explain which predictions follow stoichiometry and which depend on the chosen ATP coefficients.
Compare budgets (18,8), (18,12) and (9,12). Identify the limiting input and record both leftover amounts. Reconstruct exported carbon and explain why regenerated RuBP is not counted as a fresh net product.
Discriminate binding, relay and response mechanisms; interpret feedback and checkpoint evidence; and audit DNA, chromosome and population-age boundaries.
Compare receptor amounts 20 and 80 at ligand 2, then compare ligand 2 and 6 at fixed amount. Retain fraction and amount separately. Propose a downstream readout and a control that could reveal equal binding but different signal interpretation.
Compare hydrolysis rates 0.5 and 2 at one activation rate. Separate pulse-end fraction from the post-pulse decay. Use the sustained-input dashed curve only as a modeled counterfactual, not as a performed control experiment.
Compare receptor activity 25 with bypass absent and present; then change receptor activity to zero while retaining bypass. Record all three readouts. Design a reporter-only control that could challenge a false rescue caused by the assay.
Compare g=0 and g=2 at input 3. Retain peak and late response separately. Solve the steady equation before reading the final ledger, then explain one alternative mechanism that could generate a qualitatively similar decline.
For 2n=6 compare G1, G2, metaphase, anaphase and one daughter. Draw the boundary around each counted entity. Explain why the anaphase whole-cell count cannot be substituted into a claim about a stable daughter nucleus.
Compare stage fractions 10% and 30% at cycle duration 20 h. Calculate both estimates and state their assumptions. Design a longitudinal or independent-preparation observation that could challenge the assumed age structure; do not propose culturing or treating cells.
Compare intact and bypassed settings at damage counts 20 and 80. Keep undamaged passage, damaged passage and arrest separate. Specify an independent readout that would be required for a repair claim, and one for a survival claim.
Compare all three outcomes at 2n=6, then change the diploid complement to eight. Retain cell count, nuclear count and each nuclear chromosome count. Explain which spatial measurement distinguishes failed cytokinesis from an altered single-nucleus complement.
Derive genotype and phenotype probabilities from chromosome mechanisms, test segregation and linkage evidence, and distinguish penetrance, epistasis, environment and chromosome-count changes.
At n=3 compare all completed stages, then vary n. Keep chromosomes, DNA molecules, C amount and possible assortment combinations separate. Draw homolog separation before sister separation and explain why the combination count is not the product count of one meiosis.
Compare penetrance 1 and 0.8 with the same prior cross. Sum the posterior probabilities and distinguish the selected parent’s transmission from its carrier probability. Then vary the partner probability and explain the independence assumptions.
Compare cohort counts four and eight at p=0.25, retaining expectation, exactly-one and at-least-one probabilities. Then change p while holding cohort size. Explain an observation that would challenge the independence assumption rather than only the probability value.
Compare recessive counts 25, 30 and 35 under expected fraction 0.25. Retain each contribution and the decision rule. Then choose the alternative 0.5 model only as a separately labeled hypothesis, not as a hidden post-hoc replacement of the original claim.
Compare double-class totals zero and 20 while keeping both single-class totals fixed. Write all eight marker classes, check the total and recompute interval and outer fractions. Explain why this is a count-comparison model rather than a mechanistic claim that changing only double exchanges leaves every real process unchanged.
Compare paternal X states at maternal probability 0.5. Retain within-class and whole-cohort probabilities separately. Then change maternal probability to 0.25 and explain which arrows in the inheritance diagram change.
Compare A-function probabilities 0.5 and 0.75 at B probability 0.75. Then change B alone. Check that categories remain exhaustive and identify an intermediate readout that would discriminate the pathway from an unrelated scoring artifact.
Compare E=0 and E=4 at equal composition, then vary composition at E=2. Retain both genotype means and the mixture mean. Propose a factorial comparison that separates environmental response from composition change, with the biological unit clearly identified.
Compare all error selectors for n=3, then n=5. Draw the first- and second-division branches, check the total and combine each product with a normal n gamete. Keep product formation separate from viability and functional-gamete claims.
Trace DNA/RNA direction and molecular inventories, discriminate expression mechanisms and interpret virtual sequence/amplification/fragment evidence without overclaiming identity or function.
Compare both hypotheses after one, two and three rounds. Retain duplex fractions and heavy-strand fraction separately. Explain which observation distinguishes semiconservative from conservative and which additional generation challenges a dispersive alternative.
Compare one and three origins for 300 kb, then increase region length at fixed origin count. Draw both template orientations at one fork and label every new strand 5′→3′. State how a late-firing central origin would invalidate the equal-start prediction.
Compare exon retention and skipping with the same tail, then vary tail without changing exon choice. Keep primary RNA, mature RNA, coding length and residue count separate. Independently derive the short template example with both end labels.
Compare reference, synonymous, missense, early-stop and insertion packets at offset zero. Predict triplet groups before opening the ledger. Then use offset one as an intentionally wrong-frame contrast and explain why sequence identity without orientation/frame is insufficient.
Compare production 20 with half-life 2 against production 40 with half-life 1. Retain steady amount and approach curves. Explain why an endpoint alone cannot distinguish these conditions and why RNA equality does not establish equal protein activity.
Record all four input combinations and identify which comparison isolates repression versus positive activation. Propose an independent reporter calibration that could distinguish a biological regulatory effect from a changing detector response.
Compare intact versus disrupted A at activator one, then reduce shared activator with A intact. Retain both reporter outputs. Name a copy-number or reporter-response control needed before interpreting unequal outputs as a cis effect.
Compare alternate counts zero, ten and twenty at two assigned error probabilities. State the compared hypotheses each time. Explain why all-alternate support calls for another model rather than declaring a balanced genotype solely because it beats reference-only.
Compare efficiencies 1 and 0.8 at ten and twenty cycles. Retain the ratio to ideal doubling and identify where the formula’s fixed-efficiency assumption would need empirical validation. State separate roles for negative and positive controls.
Compare linear and circular topology at cuts1000 and3000, then move the second cut to4000. Check fragment total and distinct sizes before inspecting the annotation. Propose a second map or sequence observation that would discriminate ambiguous size patterns.
Defend a six-module cellular mechanism using causal, material, probabilistic and observation boundaries; preserve first evidence and distinguish authored learning from independent practical/mastery validation.
Compare activity100/artifact0, activity60/artifact0.10 and activity60/artifact0. Keep biological rate, sample signal, standard shift and both inverse estimates separate. Before opening the ledger, predict which contrasts distinguish activity from artifact. Then state one artifact that the matched-standard correction would not remove.
Compare survival factors1 and0.5 at r=0.2, retaining all four initial and surviving categories. Then vary r with survival fixed. Derive the selected denominator before reading the output. Propose an independent observation that could distinguish altered recombination from genotype-specific survival or scoring.
Keep predictions before comparison, complete raw records and units, explain competing models and test a changed case. Supplied and simulated data are labeled in each lesson. A saved notebook is not proof of experimental technique or correct reasoning.
Evidence to retain: Retain competing predictions, matched contrasts, standard/bypass roles and three paired preparation differences; expose a batch-confounded alternative.
Boundary: Fictional mechanisms and exact synthetic responses. Pairing is not a universal cure for interference or treatment interactions; physical preparation and independent biological data require separate evidence.
Evidence to retain: Reconstruct polymer atom/water conservation, distinguish buffer ratio from reserve, and separate hydrolytic fragmentation from conformation.
Boundary: Formal idealized chemistry without laboratory synthesis, reagent addition, protein manipulation or inferred enzyme activity.
Evidence to retain: Fit low-range standards, retain withheld residuals, invert the stated line and compare deterministic included-error bounds against an omitted sample artifact.
Boundary: No random distribution or physical assay validation is supplied. A narrow interval is conditional on the measurement model; no confidence level is assigned.
Evidence to retain: Preserve reference/object pixel ratios, test uniform resizing, distinguish resolving criteria from enlargement, and calculate area/volume under changed size and folding.
Boundary: Original schematics, not measured microscopy. Real-image calibration, segmentation and specimen preparation remain separate supervised practical evidence.
Evidence to retain: Reconstruct solute conservation over time, combine pressure and osmotic terms, contrast carrier and linear rates, and audit an uphill neutral-solute cycle.
Boundary: Well-mixed idealized compartments and supplied kinetic/energetic laws; no physical membrane, pressure or chemical manipulation.
Evidence to retain: Use two markers to challenge a target-enrichment claim and distinguish a balanced pump/leak steady state from equilibrium.
Boundary: Co-fractionation is not proof of binding, exclusive location or function; the effective pH-leak relation does not infer ATP stoichiometry.
Evidence to retain: Select and justify an initial-rate window; compare substrate-response hypotheses and exposure histories; distinguish activation-barrier changes from coupled state-dependent free energy.
Boundary: Original assigned models, not assays of a named enzyme. No enzyme handling, heating or chemical intervention is requested.
Evidence to retain: Separate ATP investment/payoff/demand; preserve diverted pyruvate; compare electron-donor/acceptor limits and proton-driving terms; reconstruct fermentation carbon and NAD+ regeneration.
Boundary: Idealized endpoint/stoichiometric ledgers do not establish actual fluxes, ATP yield, physical respiratory measurements or a unique mechanism.
Evidence to retain: Vary linear/cyclic allocation, separate water-derived oxygen from fixed carbon and determine which ATP/NADPH input limits net export.
Boundary: Productive photons and ATP coefficients are supplied assumptions. No leaf experiment, organism productivity claim or universal quantum yield is inferred.
Evidence to retain: Retain occupancy versus amount, pulse-end and decay values, upstream/downstream rescue readings and transient-versus-steady feedback comparisons; propose controls that separate biological mechanisms from detector effects.
Boundary: Original supplied models with explicit kinetic assumptions, not measurements of a named receptor or a physical cell intervention.
Evidence to retain: Draw cell/nuclear counting boundaries, compare age-distribution estimates, distinguish checkpoint passage from repair and use spatial nuclear evidence to interpret total DNA.
Boundary: No cell culture, chemical treatment or specimen experiment. Biological replication and actual supervised practical skill remain external requirements.
Evidence to retain: Trace completed meiotic stages, normalize genotype probabilities after selection, compare binomial event definitions and test a predeclared ratio under a fixed rule.
Boundary: Fictional marker probabilities and supplied counts; no breeding, family diagnosis or performed biological experiment.
Evidence to retain: Classify eight marker strings, count double recombinants, state sex-conditional denominators, audit a two-gene pathway and crossing reaction norms, and trace formal nondisjunction products.
Boundary: Virtual evidence without viability or clinical claims. Physical chromosome analysis, independent biological replication and practical skills require supervised institutional review.
Evidence to retain: Compare label-class predictions across rounds; calculate fork completion under geometry assumptions; derive a transcript with end labels; separate exon/tail/coding lengths; regroup fictional codons and stop at the first in-frame stop.
Boundary: Virtual original packets, not isotope handling, culture, engineered genes or measured molecular evidence.
Evidence to retain: Compare equal RNA pools with unequal turnover, all four operon conditions and local-versus-shared reporter effects, retaining controls and alternative mechanisms.
Boundary: No cellular intervention or gene editing. Written design and model traces do not fulfill actual laboratory participation.
Evidence to retain: Compare read hypotheses and omitted alternatives, challenge fixed amplification efficiency, and conserve fragment lengths while separating topology, fragment number and band count.
Boundary: No diagnostic interpretation, biological sample collection, primers, operating recipes or physical amplification/gel work. Privacy, provenance and independent confirmation remain necessary in real applications.
Evidence to retain: Retain activity-versus-artifact contrasts and matched standards, reconstruct initial versus surviving marker categories and identify genuinely independent evidence that separates biological mechanisms from observation/selection alternatives.
Boundary: Original calculated packets only; no culture, breeding, genetic manipulation, actual specimen observation, clinical result or certified practical participation.
Open the retained response and project workspaces. Practice, saved work and independently reviewed proficiency remain separate.
These 34 course-specific public tasks are practice, not a secure examination. Each retains up to three immutable written responses, known feedback exposure before each response, and human rubric critiques. Drafts remain editable. No text-length check or self-reported review certifies correctness, independence, laboratory skill or mastery.
Original fictional readings are untreated120, treated80, downstream bypass120 and fixed product standard120 although its reference value is100. Under a shared additive artifact, compute the matched treatment contrast. Explain what the standard diagnoses, what rescue supports only conditionally, and one observation that could challenge the shared-artifact assumption.
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Compare three separate five-residue glucose chains with one fifteen-residue acyclic chain. Count formal condensation waters and explain why formula/count evidence does not determine linkage specificity. Separately, distinguish four peptide hydrolyses in a twelve-residue no-crosslink chain from unfolding without hydrolysis.
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Two ideal1L buffers have pKa7 and pH7 but total conjugate-pair amounts4 and8mmol. A1mmol acid challenge is modeled. Compute both final ratios and pH values, and state why the same approximation must be rejected if base is exhausted.
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A model y=0.1+0.5c gives reported signal0.6AU. Signal, intercept and slope bounds are±0.02AU,±0.01AU and±0.025AU/(mmol/L). Compute nominal concentration and worst-case interval. Then consider an omitted+0.15AU sample-only artifact; compare its corrected reference with that interval and propose a discriminating validation check.
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An original schematic has a5µm bar spanning80pixels and a cell axis120pixels. Find cell length before and after uniform2× enlargement. Separately, two ideal spherical cells have radii2 and6µm at equal folding. Compare area/volume and explain why neither enlargement nor area/volume alone proves a biological transport advantage.
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A closed1L compartment begins at3mmol/L and a4L compartment at8mmol/L for a neutral permeating solute. Find their common equilibrium concentration. Separately, a plant-cell initial state has inside0.2mol/L, outside0.1mol/L, inside pressure0.3MPa and outside pressure0 at298K. UseR0.008314MPaL/(molK) to determine initial water direction; explain why this does not give final cell volume.
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A carrier model hasVmax120nmol/min and apparentKm3mmol/L. Calculate initial rate atS3mmol/L. Separately, two neutral solutes move uphill against a10-fold ratio per cycle at298K with20kJ/mol cycles of drive. UseR0.008314kJ/(molK) to estimate combinedΔG. Explain why neither a plateau nor a favorable ledger proves ATP-driven transport by a named protein.
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A protein-normalized fraction contains25% cytosolic material. Target response is20units in cytosol and100 in pure organelle material. Calculate mixture response and fold enrichment over cytosol. Separately, a maintained compartment has pump3 and effective leak coefficient1.5, with cytosolicpH7. Find compartmentpH and hydrogen-ion ratio, and bound the biological interpretation of both calculations.
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A supplied enzyme record obeys P(t)=8(1−exp(−0.5t)) µmol with time in minutes. Find the initial slope and the average rate over 1 min. Separately, a temperature-history model has undamaged rate factor 3 and active fraction exp(−0.2t); find rate factor after 5 min. Explain two different reasons a lower observed rate need not uniquely identify competitive inhibition.
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A reaction has ΔG°=+10 kJ/mol, Q=10 and T=298 K. Couple it to −20 kJ/mol using R=0.008314 kJ/(mol K). Find net ΔG. Separately, a favorable 100 mV proton voltage with no pH difference supplies energy using F=96.485 kJ/(mol V); would three protons meet a 40 kJ/mol ATP demand? State why either ledger alone is insufficient to establish a measured biological rate.
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Three µmol pyruvate undergo entry oxidation and three complete cycle turns, excluding prior glycolysis. Calculate their combined CO2, NADH, FADH2 and GTP-equivalent outputs. Then a separate ideal terminal ledger contains 5 µmol NADH and 4 µmol O2: calculate O2 consumed and electron transfer. Explain why neither ledger identifies the immediate origin of an isotopically labeled CO2 carbon or a universal ATP yield.
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Four µmol glucose are processed by standard glycolysis and entirely through the lactate branch. Calculate gross ATP, investment, net ATP, lactate, NADH regenerated to NAD+ and fermentation CO2. If other ATP demand is 10 µmol, describe the supply-demand balance without claiming a negative molecular pool.
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Use the supplied light budget: 24 µmol productive photons, linear flow 4 photons/NADPH and 8 photons/O2, ATP coefficients 3/8 per linear photon and 1/2 per cyclic photon. Compare all-linear with 50% cyclic allocation. For each case, calculate the maximum ideal Calvin net triose export using 9 ATP and 6 NADPH per triose, with adequate CO2. Identify which conclusions depend on the stipulated ATP coefficients.
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Two cell types have Kd=4 nmol/L and free ligand 4 nmol/L in excess. Receptor amounts are 40 and 120 units. Calculate occupancy and bound amounts. The first cell gives a stronger reporter response despite fewer bound units. Does that contradict the binding model? Propose one downstream and one assay explanation.
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A switch is 0.6 active when receptor activation ends; hydrolysis rate is 1 min⁻¹. Find its fraction one minute later. Separately, a sustained-input feedback model obeys 2x²+x−3=0 at steady state. Find the nonnegative response and explain why neither a pulse decay nor a decline to that plateau proves perfect adaptation under sustained input.
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An organism has 2n=8. Give G2 chromosome and complete nuclear DNA-molecule counts. After one normal nuclear division with failed cytokinesis, give cells, nuclei and chromosomes per nucleus. Contrast one sister-pair segregation error followed by successful cytokinesis. Which observation distinguishes these outcomes beyond aggregate DNA?
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A terminal stage occupies 20% of a fixed-cycle exponentially growing population with T=15 h. Compare the model duration 15log2(1.2) with the uniform-age estimate. Separately, 60 of 200 synthetic cells carry a damage label; an intact checkpoint arrests those cells but bypass lets all proceed. What can each result establish, and why are five image fields from one preparation not five biological replicates?
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A fictional Aa×Aa marker has aa penetrance0.8; other genotypes are never positive. Select a negative offspring and cross with known Aa. Compute posterior genotype probabilities, the next offspring aa probability and positive-phenotype probability. For three independent next offspring, find the probability of at least one positive result.
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Known order A–B–C and phase ABC/abc produce1000 synthetic testcross offspring: parental total700, first-interval singles100, second-interval singles160 and doubles40. Split each pair equally and name the eight marker classes. Find interval fractions, summed short-interval map length and observed outer recombinant fraction.
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A fixed recessive fraction0.25 predicts25 and75 of100 offspring; observed counts are35 and65. Calculate Pearson χ² and compare with the supplied one-df threshold3.841. Separately, a two-step pigment pathway with independent functional probabilities0.5 and0.75 yields which phenotype fractions? Explain why neither a ratio nor its rejection proves a unique enzyme mechanism.
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In the stipulated equal XX/XY model, maternal Xr probability0.25 and paternal Xr give what positive fraction in each class and overall? Separately, normal n=4 with one meiosis-II sister error in one cell gives which four formal product counts, and which counts after union with normal n=4 gametes? State what neither model predicts.
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Fictional genotype means are A=10+2E and B=14−E. At E=2 compare a50% A mixture with a75% A mixture. Then hold composition50% A and change E to4. Locate the crossing environment and state what additional data would be needed to estimate heritability.
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After three complete rounds in light precursor, compare semiconservative and conservative heavy/hybrid/light duplex fractions starting from fully heavy DNA. Separately, a400 kb linear region has four simultaneous central origins and fork speed2 kb/min. Estimate completion and identify two omissions.
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Template DNA is3′–TACCTTAAACGAATT–5′. Derive5′→3′ RNA and translate with the supplied standard assignments AUG Met,GAA Glu,UUU Phe,GCU Ala,UAA stop. Separately a processed exon total420 nt includes45 nt5′UTR,42 nt3′UTR and one stop codon, plus80 nt tail. Find mature length excluding cap nucleotide and residue count.
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RNA systems have production10 units/min with half-life4 min, or production20 with half-life2 min. Compare steady pools and fluxes. In a separate same-cell reporter model, A enhancer is disrupted while B is intact, basal10 and enhancer gain90×activator with activator0.5. Predict outputs and explain cis versus trans evidence.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A fictional operon has leak2, permissive basal8 and activator gain4. Compare inducer present/low preferred carbon with inducer absent/low preferred carbon. Separately four reads contain two alternate bases: compare balanced probability0.5 with reference-error probability0.1 using the likelihood ratio. State what neither output establishes.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Ten initial virtual copies undergo ten cycles at efficiency0.8. Compare with ideal doubling. A separate8000 bp circular molecule has cuts1000 and5000: give fragment and distinct-size-band counts, then contrast linear topology. State controls and claims still unsupported.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Two chains each contain four glucose units joined by three formal condensation links. Give total chain C/H/O inventory and released waters, then verify initial atoms are recovered when waters are included. Separately calibration signal0.2+0.02×rate gives sample0.9; a matrix-matched rate10 standard reads0.5 rather than expected0.4. Find corrected rate and name an artifact the correction excludes.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A1 L compartment initially has2 mmol/L solute and a4 L compartment has7 mmol/L. If only passive exchange occurs with fixed volumes, find total amount and eventual common concentration. Separately a fraction contains80% target organelle and20% cytosol; target concentration is100 units in pure organelle and20 in cytosol. Predict measured concentration and explain why it does not establish exclusive localization.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Three moles of glucose complete glycolysis; only half their pyruvate enters the supplied pyruvate-oxidation/citric-cycle ledger. Find net glycolytic ATP and NADH, entry/cycle CO2 and retained pyruvate carbon. Separately an ideal carbon-fixation packet has18 mol ATP and8 mol NADPH with net triose costs9 mol ATP and6 mol NADPH per mol net triose. Find net export and leftovers, naming omitted biological limits.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A supplied receptor readout30 drives relay30 and reporter2×relay. A bypass clamps relay100 without changing receptor. Predict outputs and explain what rescue does not prove. Separately a2n=8 cell completes replication, mitosis and normal nuclear division but fails cytokinesis. Give G2 DNA molecules and resulting cell/nuclear counts.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Under fully penetrant recessive aa-only phenotype in Aa×Aa, select a phenotype-negative offspring and cross with known Aa. Find its Aa probability and next-offspring aa probability. Separately AB/ab testcross has true r0.3 and AB survival0.5; others survive fully. Per1000 initial expected offspring, find survivors and the naive recombinant fraction among them.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Template3′–TACCTTAAACGAATT–5′ gives which5′→3′ RNA? Translate using AUG Met,GAA Glu,UUU Phe,GCU Ala,UAA stop. If the second codon becomes UAA, what can be stated about the supplied peptide and what remains unknown? Separately compare steady RNA pools for production10/half-life4 and production20/half-life2.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A fictional report says: “A linked marker causes enzyme failure because a selected offspring group has lower fluorescence; all repeated readings agree.” Propose a six-layer audit covering inheritance/selection, expression, protein/activity, compartment/metabolic constraints, assay calibration and independent replication. Identify what can be learned virtually and what requires genuine supervised or independent evidence.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Reviewer identity and role are declarations, not authenticated credentials. Unsaved review fields below are lost on navigation. Review every criterion with an exact quotation, calculation or evidence citation and a next step.
Integrate original first predictions, complete virtual ledgers and independent changed-case reasoning across all six modules. This authored workflow does not certify actual practical participation, learner mastery, institutional equivalence or college credit.
Choose a novel cellular claim and connect chemistry/material, compartments, metabolism, signaling/division, inheritance and molecular expression to its observation process. Identify at least two plausible alternatives.
Evidence to retain: First causal diagram, prior predictions, biological unit, safe scope and a falsifying observation retained before feedback.
Use at least one original evidence packet from each module; retain settings, raw quantities, calculations and a conflicting or rejected case. Include material/energy conservation, conditional probability and one measurement or age-distribution assumption.
Evidence to retain: Six-module notebook references, units, boundaries, uncertainty and reproducible independent calculations rather than copied final values.
Explain which controls distinguish the favored mechanism from assay, selection, environment and shared-calibration alternatives. State how actual biological replication and apparatus validation would be obtained only under qualified supervision.
Evidence to retain: Control-specific predictions, sampling/assignment plan, calibration rationale and explicit proposed-versus-performed status.
Respond to a reviewer-supplied changed packet spanning at least two modules, with original prompt and first response retained before feedback. Disclose public solution exposure and explain why the case is genuinely changed.
Evidence to retain: Versioned task record, prior reasoning, criterion-linked human evaluation and no automatic mastery award from prose submission.
Submit a first integrated report, obtain evidence-citing human critique, retain it and produce a justified revision. Separate exact model conclusions from biological claims still awaiting real evidence.
Evidence to retain: First report, raw evidence references, review, revision and one new falsifiable prediction.
Prepare a locally reviewed safe practical proposal appropriate to institutional facilities. Record execution, raw observations and supervision only if they genuinely occur; otherwise retain these as pending external requirements.
Evidence to retain: Actual instrument/specimen work, approved safety review and independent practical assessment must be supplied externally, not fabricated by virtual recipes.
Retain raw-data identifiers, provenance, units, prior predictions, methods, calculations, competing explanations and safety boundaries. State explicitly when data are simulated, supplied or genuinely observed. This saved text cannot verify a real experiment; do not invent measurements or completed supervised work. Maximum 12,000 characters; retain larger evidence files separately and cite them.
A nonempty report is only a saved submission. First and revised reports remain separate and cannot be overwritten. A critique of the first report is required before retaining one revision.
An independent reviewer changes the causal pathway, genotype/phase, compartment boundary, sequence orientation, energy budget or observation bias. The learner must defend a new mechanism and falsifying prediction using multiple representations. Renamed public examples and exposed solutions do not establish unfamiliar performance.
A human must supply the actual new task, evidence and conditions before the learner responds. The transfer-direction text is not itself an unseen assessment. Use the retained assignment form after the first project; exposed public task identifier: expanded-public:college-biology1.
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