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DAT Quantitative Reasoning study materials
DAT Quantitative Reasoning study resources

DAT Quantitative Reasoning: Survey of the Natural Sciences: DAT Study Guide

DAT Quantitative Reasoning · Work through your exam, one topic at a time.

All guide sections

Survey of the Natural Sciences: DAT Study Guide

What the DAT Survey of the Natural Sciences covers

The Survey of the Natural Sciences (SNS) is a 100-question, 90-minute section split into Biology (40), General Chemistry (30), and Organic Chemistry (30). It rewards broad, accurate recall and fast application of first-year science, not lab technique or research design.

Core rules and high-yield concepts

  • Biology: membrane transport and osmosis, enzyme kinetics (Km, Vmax, inhibition), Mendelian and molecular genetics, DNA replication/transcription/translation, cell cycle, major organ-system physiology, hormone feedback, evolution mechanisms, and population ecology.
  • General chemistry: dimensional analysis and limiting reagents; gas laws; thermochemistry (ΔG = ΔH − TΔS); equilibrium and Le Chatelier; acid-base/pH and buffers; kinetics; electrochemistry; solutions and colligative properties.
  • Organic chemistry: hybridization and geometry; resonance and aromaticity; R/S and E/Z; conformations; SN1/SN2/E1/E2; alkene and carbonyl addition; IR and 1H NMR.
  • Many items are two-step: identify the concept, then calculate or trace a pathway. For physiology, follow stimulus → sensor → hormone → target → effect; for chemistry, write the balanced equation first. There is no penalty for wrong answers, so leave nothing blank.

Worked example

Methane burns: CH4 + 2 O2 → CO2 + 2 H2O. If 4.0 g CH4 (0.25 mol) reacts with 16.0 g O2 (0.50 mol), what mass of CO2 forms? The stoichiometric ratio is 1 CH4 : 2 O2, and 0.25 mol CH4 needs exactly 0.50 mol O2, so neither reagent is in excess. CO2 moles = 0.25 mol; mass = 0.25 × 44.0 = 11.0 g.

Traps that cost marks

  • Choosing a mechanism by name instead of by substrate, nucleophile/base strength, solvent, and temperature.
  • Forgetting that ΔG sign depends on both enthalpy and entropy, and on T.
  • Confusing mitosis with meiosis or homologous with sister chromatids.
  • Using mole ratios backward in limiting-reagent problems.
  • Overinvesting in low-yield taxonomy while missing physiology and carbonyl chemistry.