Genétic problems or diseases
They come from crementation which is when disolved minerals are deposited in tiny spaces...
Attached is a picture/diagram of both a gram negative bacteria and a gram positive bacteria. This question most likely pertains to gram negative bacteria as only gram negative bacteria as an outer lipopolysaccharide (LPS) membrane.
It should be noted that there must be an error in the question as the bacterial cell wall comprises of the peptidoglycan layer (for gram positive) or the outer membrane plus the peptidoglycan layer (in gram negative). The better question would be what is the space between the cell wall and the plasma membrane in a prokaryotic cell, and the answer is the periplasmic space.
Answer:
The "tail" of the molecule is made up of two fatty acids, which are hydrophobic and do not dissolve in water. Following the rule of "like dissolves like", the hydrophilic head of the phospholipid molecule dissolves readily in water.
Nonpolar Fatty Acids
I Hope this answers your question :)