hydrophilic vs hydrophobic parts of lipid bilayer & why the location of each makes sense NEED HELP ASAP

In a lipid bilayer, the hydrophilic part is the head, and the hydrophobic is the tail. This location makes sense because the plasma membrane has a barrier that has a selective permeability so it selects what goes in and what goes out of the lipid bilayer.

characterization of nanoparticles is a critical step in nanomaterial production as it provides information of dimension, morphology, surface charge, distribution and degree of surface functionalization.

"do a testcross with a homozygous recessive plant."