• What subject is it (e.g., Anatomy, Biochemistry, History, Statistics, etc.)?
• Is there a syllabus, course outline, or list of topics you've been given?
• What level is the exam (undergrad, med school, board exam like USMLE, etc.)?

Anatomy - High-Yield Topics

• Thorax: Heart anatomy (chambers, valves, coronary arteries), lungs and pleura, mediastinum divisions
• Abdomen: Peritoneum (retroperitoneal vs. intraperitoneal organs), GI tract blood supply (celiac, SMA, IMA), portal circulation, inguinal canal
• Limbs: Brachial plexus (roots, trunks, divisions, cords, branches - know nerve injuries like Erb's and Klumpke's), lumbosacral plexus, common nerve injury patterns (radial, ulnar, median, femoral, sciatic)
• Head & Neck: Cranial nerves (origin, function, and what happens when each is damaged), carotid arteries, thyroid/parathyroid relations
• Pelvis: Pelvic floor muscles, urogenital triangle, femoral triangle

• Spinal cord tracts (dorsal columns vs. spinothalamic) - know what deficits arise from lesions
• Brain lobes and their functions
• Ventricular system and CSF flow
• Blood-brain barrier

• Cell types in each tissue (epithelium types and where they're found)
• Connective tissue components
• Basic histology of major organs (liver, kidney, lung, skin)

Biochemistry - High-Yield Topics

• Glycolysis & gluconeogenesis: Key enzymes, irreversible steps, regulatory enzymes (hexokinase, PFK-1, pyruvate kinase)
• TCA cycle (Krebs): Inputs, outputs, regulated steps, energy yield
• Oxidative phosphorylation: Electron transport chain complexes, ATP synthase, inhibitors (cyanide, CO, oligomycin)
• Fatty acid metabolism: Beta-oxidation vs. fatty acid synthesis (where each occurs, what cofactors are needed), ketone body formation
• Amino acid metabolism: Essential vs. non-essential, urea cycle disorders, transamination, deamination
• Glycogen metabolism: Glycogen storage diseases (von Gierke, McArdle, Pompe, Cori)

• DNA replication, transcription, translation - enzymes involved at each step
• DNA repair mechanisms
• Mutations (missense, nonsense, frameshift) and their consequences

• Fat-soluble: A, D, E, K - functions and deficiency diseases
• Water-soluble: B1 (thiamine - beriberi, Wernicke's), B2, B3 (niacin - pellagra), B6, B9 (folate - neural tube defects), B12 (pernicious anemia), C (scurvy)

• Michaelis-Menten kinetics (Km, Vmax)
• Competitive vs. non-competitive inhibition
• Allosteric regulation

• LDL, HDL, VLDL, chylomicrons - what they carry, where they go
• Familial hypercholesterolemias

Physiology - High-Yield Topics

• Cardiac action potential (phases, ion channels involved) - especially pacemaker vs. contractile cell differences
• Cardiac output = Heart rate x Stroke volume; Frank-Starling law
• Pressure-volume loops
• Blood pressure regulation (baroreceptors, RAAS)
• ECG interpretation basics

• Lung volumes and capacities (TV, IRV, ERV, RV, FRC, TLC, VC)
• V/Q ratio and V/Q mismatch
• Oxygen-hemoglobin dissociation curve (shifts left/right and why)
• Acid-base disorders (respiratory vs. metabolic acidosis/alkalosis)

• Nephron segments and what each reabsorbs/secretes
• Starling forces (glomerular filtration)
• Renin-angiotensin-aldosterone system
• Acid-base balance - kidneys' role

• Resting membrane potential and action potential (Na+/K+ ATPase, gating)
• Synaptic transmission (neurotransmitters, receptors)
• Neuromuscular junction

• Hormones: gastrin, secretin, CCK, GIP - stimuli and effects
• Phases of digestion (cephalic, gastric, intestinal)

• Insulin vs. glucagon: stimuli for release, effects on metabolism
• Thyroid hormones: synthesis, regulation, effects
• Cortisol and the HPA axis
• Growth hormone and IGF-1

Study Tips for All Three

1. Integrate across subjects - e.g., learn the kidney in anatomy (histology of nephron), physiology (what each segment does), and biochemistry (acid-base chemistry) together. This sticks better and reflects how exams test.
2. Draw it out - brachial plexus, TCA cycle, and cardiac action potential are all much easier when drawn from scratch repeatedly.
3. Use mnemonics for nerve/vitamin lists - there are well-established ones for cranial nerves, brachial plexus, and B vitamins.
4. Past questions - if your school provides them, prioritize those. Exam writers often recycle concepts.