A cell structure which living cells cannot function without is the mitochondria.
This mitochondria is regarded as the power house of every living cell.
All cells need energy through respiration and the site where these activities are done is he mitochondria.
This means that the main function of mitochondria is that it serves as the power house energy of cells
A cell can simply be defined as the simplest unit of life. All living organisms be it unicellular or multicellular organisms is made up of cell.
So therefore, a cell structure which living cells cannot function without is the mitochondria.
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