Abiologist is studying a structure that is made up of two layers of phospholipids. what is she most likely studying? dna molecules cell membranes fats wax

The structure the biologist is most likely studying is the cell membrane. The cell membrane is made up of lipid bilayers {two layers} with embedded proteins. The basic structure of the cell membrane is the phospholipid bilayer which forms a balance barrier between two aqueous environment. This structure optimizes the cell membrane to control the movement of substances in and out of the cell.

Covalent bond is the correct answer