Which statement best describes receptor-mediated endocytosis?

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Receptor-mediated endocytosis is a highly selective uptake process driven by specific interactions between a ligand and its receptor. When a ligand binds its receptor on the cell surface, the receptor–ligand complexes cluster into small, coated pits lined with proteins like clathrin. These pits bend inward to form vesicles that carry the cargo into the cell. After the vesicle forms, the clathrin coat is removed, and the cargo is delivered to early endosomes and then to lysosomes for processing, while receptors are recycled back to the membrane for another round of uptake. This mechanism explains how molecules such as LDL particles are internalized efficiently even at low concentrations, because uptake depends on the precise fit between ligand and receptor.

Non-specific uptake lacks this receptor-driven selectivity, so it doesn’t concentrate particular ligands in coated pits. It’s not restricted to plant cells, and while energy is required for vesicle formation and trafficking, the defining feature is the specific receptor–ligand recognition and the involvement of clathrin-coated pits and vesicles.