Lipid metabolism — Flashcards

Flashcard 281: What substrate accumulates in the lysosomes of a patient with Tay-Sachs disease? _____

Answer: GM2 ganglioside

Flashcard 282: What salivary enzyme begins the initial digestion of fats? _____

Answer: Lingual lipase

Flashcard 283: What do fungal plasma membranes contain that others lack?_____

Answer: Ergosterol

Flashcard 284: Primary carnitine deficiency is characterized by muscle weakness and hypotonia, which is provoked by prolonged _____ (especially if fasting)

Answer: exercise

Flashcard 285: The main component of VLDL is _____ (60%)

Answer: triglycerides

Flashcard 286: Carnitine acyltransferase-1 (CPT-1) is regulated via negative feedback by _____

Answer: malonyl CoA

Flashcard 287: Which lysosomal storage disease is characterized by a cherry red spot on the macula and no hepatosplenomegaly? _____

Answer: Tay-Sachs disease

Flashcard 288: Fatty acyl-carnitine is transported from the intermembrane space into the mitochondrial matrix via the _____ transporter

Answer: Carnitine-acylcarnitine translocase

Extra: The **carnitine shuttle** involves: 1. **CPT I:** Located on the outer mitochondrial membrane; converts Acyl-CoA to Acyl-carnitine. 2. **Carnitine-acylcarnitine translocase:** Located on the inner mitochondrial membrane; transports Acyl-carnitine into the matrix in exchange for carnitine. 3. **CPT II:** Located on the inner mitochondrial membrane; converts Acyl-carnitine back to Acyl-CoA for beta-oxidation.

Flashcard 289: Thromboxane A2 (TXA2) is synthesized by the platelet enzyme _____

Answer: cyclooxygenase-1 (COX-1) (specific)

Flashcard 290: Which apolipoproteins (4) do chylomicrons express on their surface? _____

Answer: Apolipoproteins A-I, B-48, C-II, and E