Does Mitochondria Have Double Membrane? 5 Important Facts

The Mitochondria are formed via the symbiotic relationship with bacterial cells to do the primary role of energy metabolism and respiration. Let us talk about this in detail.

The mitochondria have a double membrane with a large surface area having two lipid bilayers consisting of a plasma membrane and outer membrane with enclosed one unique compartment referred to as an intermembrane.

The double membrane is a direct result of endosymbiosis which gives the entire membrane structure of mitochondria.Let us learn this in detail.

Do mitochondria have a single or double membrane?

The mitochondria act as a powerhouse of the cell. They are essential for different kinds of cellular activity such as ATP synthesis. Let us discuss this in brief.

The mitochondria have a double membrane with a total of four compartments including an outer membrane that is very smooth, an inner membrane, an inter-membrane space, and a matrix.

A primitive eukaryotic cell engulfed a prokaryotic cell and over time, both cells evolved into a symbiotic relationship. The double membrane is the result of this engulfment.

Why do mitochondria have a double membrane?

The mitochondria itself is a cell that lives in another cell.It is mainly derived from an original free-living gram-negative bacteria. Let us talk about this in detail.

The mitochondria have a double membrane because it acts as a barrier during setting up an electrical potential that drives other chemical reactions. The production of adenosine triphosphate (ATP) or their particles and the process of cellular respiration mainly occurs in the membrane region of mitochondria.

Endosymbiosis from Wikipedia

The membrane contains a matrix having a DNA molecule inside it. The space between inner and outer membrane space is known as an Inter membrane space.

Functions of the double membrane in mitochondria

The double membrane of mitochondria has different functions which are mentioned below.

  1. It regulates the molecules that come in and out of the organelle during cellular respiration and ATP synthesis
  2. It helps in oxidative phosphorylation and the electron transport system
  3. It acts as a barrier to make concentration gradient with positive ions on one side and negative ions on the other.

Structure of double membrane in mitochondria

All kinds of cellular activity of mitochondria are intimately connected with its double membrane structure. Let us explore this in detail.

The mitochondrial double membrane looks like a large wrinkled bag that is packed inside a smaller unwrinkled bag. Both have very different structures and functions which are shown in the image below.

Structure of Mitochondrial membrane from Wikipedia

Does mitochondria have a double lipid bilayer?

The mitochondrial membrane has one specific structure which is hydrophobic from the inner and hydrophilic from the outside of the membrane. Let us learn about this in detail.

The mitochondrial membrane consists of the two phospholipid bilayer, that is very close to the outer membrane as well as the cytoplasm. Due to the accurate arrangement of lipid molecules in the membrane, It can only allow the specific size molecule inside the mitochondria.

Structure of Mitochondria from WIkipedia

The membrane also has some protein channels and carriers through which it can use transport mechanisms by the use or without the use of energy.


From the above article, It can be concluded that the mechanism of adenosine triphosphate (ATP) synthesis occurs very accurately due to the presence of a double membrane that prevents the entry of chemicals and other undesired molecules into the mitochondria.

Scroll to Top