Why does mycoplasma have tri-layered cell membrane ? Can you explain 

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Please find your answer below to the asked query:

Mycoplasma or PPLO , the smallest organism is composed of two electron-dense layers with a less dense layer in between.
 This three-layered structure corresponds to the 'unit membrane ' which covers cells .Each difffernt layer has different constituents so thus serve as protective and nutional layer.

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