Lipids form the bilayer of cell membrane which act as a partially permeable mmbrane of cell to control the substances moving in and out of the cell.
The protein structures can be classified into four levels, namely the primary structure, secondary structure, tertiary structure, and quaternary structure. The primary structure is the simplest of all the structures. When all the hydrogen bonds are disrupted, the secondary, tertiary and the quaternary structures gets disrupted, which leads the protein to the most simplest structural form, that is the primary structure. In this structure, the a carbon atom is bonded to hydrogen atom, carboxyl group, amino group, and an 'R' group.
B. ATP synthase. The purpose of the hydrogen gradient is to take advantage of molecules' tendency to move from areas of higher concentration to areas of lower concentration. ATP synthase lets hydrogen ions flow through it to the matrix, and the energy from this flow is used by ATP synthase to synthesize ATP.