Hey there, 

As per your query I would like to tell you that according to your question. The cell wall of gram positive bacteria consists of many interconnected layers of peptidoglycan and lack of outer membranes. Peptidoglycan prevents osmotic lysis in the hypotonic environment in which most bacteria live. 

In my thoughts in your module, there are some errors in printing. 

Hopefully it's will be useful to you.