Question

in a bilayer the hydrophilic heads of the phospholipids will want to be touching water at all times. so the first layer will form a ring with the heads facing water. this leaves the hydrophobic tails touching the inside of the circle. however the intracellular environment of a cell is aqueous or water-based. so the tails aren't going to like this. how can we account for it? well that's why a second layer of phospholipids is so important.

Answer 1

yes, phospholipid bilayer has two important characteristics:
1.protects the cell from surrounding aqeous env.

2.permeability- to maintain negative charge towards cytoplasm.

if single layer of p.lipids is present then hydrophobic chains will form micelle like structures, which donot allow the formation of cell membrane.

the other reason is to hold the integral proteins that acts as channels for the flow of ions along their conc. gradient to maintain negative charge towards cytosol.