A lipoprotein membrane that encloses many cells and cell organelles and is composed of two electron-dense layers enclosing a less dense layer.
- ‘In the area of the tight junction (zonula occludens) the two unit membranes approach each other and appear to merge revealing only three dense lines (instead of four).’
- ‘The inner membrane composition is phospholipid with many integral proteins (as in bacterial unit membranes)’
- ‘A cholesterol-containing unit membrane defines the cell body; however, there is no periplasm providing rigidity for the cell.’
- ‘The ER is made up of two unit membranes enclosing a lumen in between.’
- ‘In the depth of the insulating layer of myelin there are major dense lines formed by the apposition of the cytoplasmic faces of unit membranes, while faint intraperiod lines are formed by apposition of outer faces.’