Final answer:
Lipid membranes, also known as semipermeable membranes, selectively allow certain substances to pass through, playing a crucial role in maintaining homeostasis.
Step-by-step explanation:
Lipid membranes, well-known for their selective permeability, are also referred to as semipermeable membranes. This intrinsic property allows them to control which substances can freely pass through. The tightly packed phospholipid bilayer, with hydrophobic tails and hydrophilic heads, creates a barrier that small, nonpolar materials such as lipids and certain gases can cross without help. Larger or water-soluble substances like glucose or amino acids, however, require assistance to move across this barrier. This critical function of the lipid bilayer is essential for maintaining homeostasis within cells and, by extension, the entire organism.