Learn / FMK
Every FMK condition
299 diseases, deficiencies, toxicities and drug mechanisms harvested from every FMK deck — the ones sprinkled through a single bullet as much as the ones with their own slide. Pick what you're given and what you have to name, or let it cycle; distractors come from the same category so you have to discriminate (hypoketotic vs. ketotic hypoglycemia, which GSD, which urea-cycle enzyme…). Every answer shows the whole card with the lecture and slide.
Toxin/Drug · FMK 02.4
Cyanide poisoning Acquired / not inherited
Defect / target: Complex IV (cytochrome c oxidase) — CN⁻ binds Fe³⁺ in heme a₃
Mechanism: Cyanide blocks O₂ reduction at Complex IV so electron flow stops, ATP synthesis fails and cells shift to anaerobic glycolysis with lactic acidosis despite adequate O₂ delivery.
↑ Accumulates: NADH, lactate· ↓ Deficient: ATP
Presentation: confusion, coma, house-fire (polyurethane smoke) exposure, bitter-almond odor, industrial exposure
Labs: ↑ lactate (anion-gap acidosis), ↑ mixed venous O₂ (cells cannot use O₂), normal PaO₂
Treatment: Hydroxocobalamin + 100% O₂
Cyanide binds Fe³⁺, CO binds Fe²⁺
Learn the mechanism: Electron transport & OXPHOS →Reasoning case →
FMK 02.4 Mitochondrial Metabolism and Energy Disorders · slide 9, 11, 13, 17, 20, 25