Final answer:
Receptor-mediated endocytosis is a process in which extracellular substances are internalized in clathrin-coated vesicles. LDLs are taken into cells through receptor-mediated endocytosis, as are some viruses. Internalized vesicles fuse with lysosomes, which mature into endosomes.
Step-by-step explanation:
Receptor-mediated endocytosis is a cellular process in which extracellular substances are internalized in clathrin-coated vesicles. This process allows cells to selectively take in specific substances by binding to receptors on the cell membrane. Low-density lipoproteins (LDLs) are indeed taken into cells by receptor-mediated endocytosis.
Additionally, some viruses are also taken into cells through this mechanism. In receptor-mediated endocytosis, the internalized vesicles do fuse with lysosomes, which then mature into endosomes.