The cell membranes are responsible for controlling the movement of substances in and out of the cell.

The doctor examined the patient's mucous membranes for any signs of infection.

The nictitating membranes of birds protect their eyes while flying.

The serous membranes protect and lubricate the organs in the body.

The doctor explained that the virginal membranes are thin layers of tissue that partially cover the opening of the vagina.

The plasma membranes surround and protect the cells.

The rupture of membranes can occur spontaneously during labor.

The synovial membranes protect and lubricate the joints.

The nuclear membranes protect the genetic material inside the nucleus.

The Reissner's membranes in the cochlea help separate the scala media from the scala vestibuli.