Hii

Bacteria are unicellular organisms that have a variety of sizes, shape, and envelope structures

Ultra structure of  bacteria cell  is the gram-positive cell wall consists of a single 20 to 80 nm thick homogeneous peptidoglycan or murein layer lying outside the plasma membrane

The gram negative cell wall is quite complex. It has a 2 to 7 nm peptidoglycan layer surrounded by a 7 to 8 nm thick outer membrane.

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