Fatty acid synthesis, beta-oxidation, and lipoprotein metabolism tested on USMLE Step 1.
40 cards · basic cards · AI-written, checked twice. Edit anything.
- What is the rate-limiting enzyme of fatty acid synthesis?
- Acetyl-CoA carboxylase
- What vitamin-derived cofactor does acetyl-CoA carboxylase require?
- Biotin
- What is the direct product of the acetyl-CoA carboxylase reaction?
- Malonyl-CoA
- Which metabolite allosterically activates acetyl-CoA carboxylase?
- Citrate
- Which metabolite provides feedback inhibition of acetyl-CoA carboxylase?
- Palmitoyl-CoA (long-chain fatty acyl-CoA)
- Which enzyme phosphorylates and inactivates acetyl-CoA carboxylase during fasting or exercise?
- AMP-activated protein kinase (AMPK)
- What multi-enzyme complex assembles palmitate from acetyl-CoA and malonyl-CoA units?
- Fatty acid synthase
- In which cellular compartment does fatty acid synthesis take place?
- The cytoplasm
- In which cellular compartment does fatty acid beta-oxidation take place?
- The mitochondrial matrix
- What pathway is the main source of NADPH used in fatty acid synthesis?
- The pentose phosphate pathway (HMP shunt)
- What shuttle moves acetyl-CoA from the mitochondria to the cytoplasm for fatty acid synthesis?
- The citrate shuttle
- Which enzyme cleaves cytoplasmic citrate into acetyl-CoA and oxaloacetate?
- ATP-citrate lyase
- What molecule is required to shuttle long-chain fatty acids into the mitochondria for oxidation?
- Carnitine
- What is the rate-limiting enzyme of fatty acid beta-oxidation?
- Carnitine palmitoyltransferase I (CPT-I)
- Which metabolite inhibits CPT-I, preventing fatty acid oxidation when synthesis is active?
- Malonyl-CoA