Section III · high-yield map
Section III is written so that a candidate who reasons well beats one who has memorised more. What follows is not a syllabus to work through in order, but the set of things that keep reappearing.
Before the content
These pay more per hour than any topic below, since they apply to every question in the section whatever its content.
Before calculating, check what units the answer must be in and whether your expression produces them. This catches most arithmetic slips, and often identifies the right option without the sum: if the answer must be in watts and only one option is dimensionally a power, you are done.
Most quantitative work here is a proportionality in disguise. If force goes with the square of speed and power is force times speed, power goes with the cube, so doubling speed costs eight times the power. Chain the relationships rather than computing intermediate values.
Note what is plotted, in what units, and whether either axis is logarithmic. Then look at the extremes, since that is where the question usually lives: saturation, thresholds, intercepts, plateaus.
When a stimulus gives two conditions, find the single thing that differs. Comparative questions are asking what that difference caused, which is about as far as the GAMSAT takes experimental design.
About 40%
The most learnable part of the section. With limited time, spend it here.
| Chemistry | Depth it is tested to |
|---|---|
| Acid–base | pKa as a ranking tool, Henderson–Hasselbalch, buffers, titration curves. Half-equivalence gives pKa; weak acid equivalence sits above pH 7. Appears constantly. |
| Equilibrium | Le Chatelier qualitatively: which way does the system shift, and why. Numerical K calculations are rare; directional reasoning is common. |
| Organic structure | Recognise functional groups on sight. Isomerism: structural, geometric, enantiomers, chirality centres. You will be asked to count them. |
| Acidity & basicity | Stability of the conjugate base decides everything: resonance, induction, electronegativity, size. Worth more than any reaction mechanism. |
| Reaction mechanisms | Nucleophile, electrophile, leaving group as concepts. SN1 vs SN2 conditions. Curly arrows appear, but reasoning about charge usually suffices. |
| Thermodynamics | ΔG = ΔH − TΔS and what each sign means for spontaneity. Coupling of favourable and unfavourable reactions. |
| Kinetics | Rate versus equilibrium, a distinction tested directly. Catalysts lower activation energy and change neither ΔG nor the position of equilibrium. |
| Stoichiometry | Moles, limiting reagent, concentration, dilution. Simple, and a reliable source of marks under time pressure. |
About 40%
Broad and shallow. Revising it topic by topic is inefficient, and the return comes from practice questions, since what is tested is the reading of unfamiliar biological data rather than the recall of familiar facts.
| Biology | Depth it is tested to |
|---|---|
| Membranes & transport | Passive vs active, osmosis and tonicity, concentration gradients. Predict the direction water moves and why. |
| Enzymes | Km and Vmax read off a curve; competitive vs non-competitive vs uncompetitive inhibition. Among the most frequently examined biology topics. |
| Metabolism | Glycolysis, Krebs and the electron transport chain at the level of inputs, outputs and location. Memorising intermediates is wasted effort. |
| Genetics | Mendelian ratios, pedigree reading, dominance and linkage. Central dogma, transcription, translation, and what a given mutation does to a protein. |
| Physiology | Cardiovascular, respiratory, renal, nervous and endocrine, treated as systems with feedback loops. Action potentials and oxygen dissociation curves recur. |
| Homeostasis | Negative feedback as a reasoning pattern. Given a perturbation, predict the corrective response. Transfers across every organ system. |
| Immunology | Innate vs adaptive, antibodies, clonal selection, vaccination. Tested lightly but appears. |
| Evolution | Selection pressure, fitness, drift, speciation. Usually presented as a data-interpretation problem rather than a recall question. |
About 20%
The smallest body of content and the most mechanical. If physics is your weak point, this is the highest-return weekend in your preparation.
| Physics | Depth it is tested to |
|---|---|
| Kinematics & forces | The suvat equations, Newton's three laws, free-body diagrams, resolving on inclines. Mechanical and reliable. |
| Work, energy, power | Conservation of energy, P = Fv, W = Fd, efficiency as output over input. Energy arguments often bypass a long calculation entirely. |
| Momentum | Conservation in collisions; elastic vs inelastic. Impulse as force × time. |
| Fluids | Pressure with depth, density, buoyancy, continuity and flow rate. Frequently dressed up as physiology, in blood vessels and lungs. |
| Electricity | Ohm's law, series and parallel, power dissipation. Circuit questions are self-contained gifts if you know the two rules. |
| Waves & optics | Frequency, wavelength, speed; reflection, refraction, lenses. The Doppler effect appears in clinical dress. |
| Radioactivity | Alpha, beta, gamma; half-life as repeated halving. Nearly always solvable by counting halvings rather than by using the exponential. |
Skip
Named organic reactions beyond the common few, glycolytic intermediates, specific constants, long derivations, and anything needing a calculator you will not have.
Where a fact is both required and obscure, the stimulus supplies it. Trusting that is what lets you move quickly.