Anatomy and Physiology: Structure Serving Function
Anatomy and physiology questions often test applied relationships: which nerve, which vessel, which organ system. Anchor revision in clinically relevant anatomy. For the upper limb, know the brachial plexus divisions and the consequences of injury at each level. For the abdomen, know the blood supply of the gut (celiac, superior mesenteric, inferior mesenteric) and the referred pain patterns from embryologic origin - foregut pain is epigastric, midgut is periumbilical, hindgut is suprapubic. This explains the migration of appendicitis pain.
Physiology essentials
Understand cardiac output (heart rate times stroke volume), preload and afterload, and how the Frank-Starling relationship explains fluid responsiveness. Know the nephron segments and where each diuretic acts. Understand the countercurrent multiplier and the role of antidiuretic hormone. Respiratory physiology: ventilation-perfusion matching, oxygen-hemoglobin dissociation curve shifts, and the difference between hypoxia and hypoxemia.
Neuroanatomy
Localize lesions by pattern: upper motor neuron signs are spasticity and hyperreflexia; lower motor neuron signs are flaccidity and atrophy. Cranial nerve deficits localize brainstem lesions.
Traps
Questions may present a lesion and ask for the first structure affected or the most likely deficit. Draw the pathway rather than guessing.
Rule of thumb
When unsure, trace the pathway from origin to target. Anatomy questions usually reward knowing the route, not isolated names.