Unlike animal cells, bacteria have a porous cell wall surrounding their plasma membrane. the cell wall may bacteria survive in environment.

 Unlike animal cells, bacteria have a porous cell wall surrounding their plasma membrane. The cell wall may help bacteria survive in hostile environment.

Explanation:

Diferent from cells of higher organisms, the bacterium is faced with an unpredictable and often hostile environment.  

Bacteria  have evolved in order to survive, a sophisticated and complex cell envelope that protects them, but at the same time allows selective passage of nutrients from the outside and waste products from the inside.

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