Metabolism USMLE Step 1 Practice Question
Liver cells in culture were kept at 0°C (32.0°F) and treated with trypsin to digest the receptors on the cell surface. The temperature was then raised to 37.0°C (98.6°F), and radioactive LDL was added to the culture media. Several hours later, the labeled LDL was found to be inside the cells. Which of the following represents the process of LDL uptake by hepatocytes?
Answer choices
- AReceptor-mediated endocytosisCorrect answer
- BActive transport
- CPhagocytosis
- DFacilitated diffusion
- EPinocytosis
- FClathrin-independent endocytosis via caveolin-1
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