A cell conducts endocytosis by invaginating its plasma membrane to engulf substances from the extracellular environment. Here's a breakdown:

* Invagination: The cell membrane folds inward, creating a pocket-like structure.

* Encapsulation: The pocket then closes around the substance, forming a vesicle (a small, membrane-bound sac) inside the cell.

* Transport: The vesicle carries the engulfed substance to its destination within the cell.

There are three main types of endocytosis:

* Phagocytosis: The cell engulfs large particles, such as bacteria or cell debris.

* Pinocytosis: The cell engulfs fluids and dissolved substances.

* Receptor-mediated endocytosis: The cell engulfs specific molecules that bind to receptors on the cell membrane.

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