Exocytosis is the process by which cells release materials from the cell into the extracellular space. It is the opposite of endocytosis, which is the process by which cells take in materials from the extracellular space.

Here's a simple breakdown:

* Endocytosis: Bringing things into the cell. Think of it like eating.

* Exocytosis: Sending things out of the cell. Think of it like spitting out a seed.

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