Organelles

- Overview 

In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name organelle comes from the idea that these structures are part of a cell, just as an organ is to a body, so organelle, the suffix -elle is a small word. Organelles are either individually enclosed in their own lipid bilayers (also known as membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane-bound organelles). Although most organelles are functional units within a cell, some functional units that extend outside the cell are commonly referred to as organelles, such as cilia, flagella and archaea and hair follicles. 

An organelle is a subcellular structure that has one or more specific jobs in a cell, just like an organ does in the body. The more important organelle is the nucleus, which stores genetic information. mitochondria, which produce chemical energy; and ribosomes, which assemble proteins. 

Organelles are specific structures within a cell, and there are many different types of organelles. Organelles are also called intracellular vesicles. They do have an important function because we need to divide all the functions inside the cell. Therefore, there needs to be a membrane around the mechanisms that make different products within the cell. So really, organelles are all membrane bound. They separate one function from another. 

For example, mitochondria have the function of producing energy, while lysosomes have the function of producing small molecules from large molecules, breaking these things down. They need to be compartmentalized because all the pathways in the mitochondria, all the proteins and enzymes in them, need to convert one chemical into another, and the lysosomes need an acidic pH. If these things are mixed together, no functionality will be produced at all. So this is really the heart and soul of organelles: being compartmentalized and allowing high concentrations of proteins or acids, or whatever creates this environment, so that specific functions can be performed.

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