Organelles are specialized structures within a cell that perform specific functions, much like organs do in a multicellular organism. They are enclosed in membranes and are found in both eukaryotic and prokaryotic cells, although prokaryotic cells have fewer and simpler organelles.

Here are some examples of organelles:

* Nucleus: Contains the cell's genetic material (DNA).

* Mitochondria: Powerhouse of the cell, responsible for energy production.

* Ribosomes: Sites of protein synthesis.

* Golgi apparatus: Modifies and packages proteins for transport.

* Endoplasmic reticulum: Network of membranes involved in protein and lipid synthesis.

* Lysosomes: Contain enzymes for breaking down cellular waste.

Let me know if you'd like to learn more about specific organelles!