Which compounds primarily make up the plasma membrane?

The plasma membrane is primarily composed of proteins and lipids, which together create a bilayer structure that serves as a barrier and a functional interface between the interior of a cell and its external environment. Lipids, particularly phospholipids, form the foundational bilayer due to their hydrophilic (water-attracting) heads and hydrophobic (water-repelling) tails, which allows for the formation of a semi-permeable membrane. This bilayer structure is essential for maintaining the integrity of the cell while allowing selective transport of substances.

Proteins embedded within this lipid bilayer play crucial roles in various cellular functions, including signaling, transport, and structural support. These proteins can act as receptors for hormones, channels for molecules to enter or exit the cell, and enzymes that facilitate biochemical reactions. The combination of these proteins and lipids creates a dynamic and functional plasma membrane that is vital for cell communication and homeostasis.

The other options do not accurately represent the primary components of the plasma membrane. Carbohydrates do play roles in cell recognition and signaling when attached to proteins or lipids, but they do not constitute the primary structure of the membrane. Nucleic acids are involved in genetic information storage and transfer, while proteins and lip