Learn / Metabolism
Metabolic pathways
Every FMK pathway as a clickable map. Pick one pathway to hammer it — next step, enzyme, regulator, cofactor, and the facts that get tested (NADPH and who needs it, rate-limiting steps, deficiencies) — or set it to all pathways for a mixed drill. Every answer says which enzyme and which pathway.
Sphingolipid degradation & the sphingolipidoses · Lysosome (degradation); synthesis in ER → Golgi. Enzymes sit beside the arrows, ★ = rate-limiting, ⊕/⊖ = activators/inhibitors (toggle), −ATP +NADH = what the step spends and makes (toggle ⚡), dashed = allosteric signal, shaded bands = compartment. Drag to pan.
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Sphingolipid degradation & the sphingolipidoses
Sphingosine
Made from Ceramide (sphingosine + fatty acid) by Ceramidase
Ceramidase · irreversible — Sphingolipid degradation & the sphingolipidoses
Cofactors: H₂O
Deficiency: Farber disease (AR, ASAH1) — ceramide accumulates: hoarse cry from laryngeal nodules, painful swollen joints with deformity, subcutaneous nodules over the joints and spine
The last hydrolysis: ceramide is split back into its two parts.
Condition cards:Farber disease →