Science

When it comes to the biology of living organisms, there is a relationship between their structure and function. Despite whether it's on a cellular or larger scale this connections still remains to exist. Even on a more deeper foundation than cells when examining the mitochondria, a component of a cell, this relationship still prevails.

The mitochondria belongs to almost every eukaryotic cells. The main function of mitochondria is to provide energy for the cell by converting broken down glucose into ATP.

What helps support for this sophisticated process is its anatomy. A mitochondrion contains two main membranes composed of phospholipid bilayers and protein. This encloses the entire organelle and contains porin protein molecules that serve as diffusion channels for minute protein molecules across the membrane. Larger molecules can enter only if their signaling sequence can bind to a large translocate protein in the outer membrane. This contains about 1/5th of the mitochondrion protein, but has no porin proteins, and includes several hundred polypeptides. The inner membrane is impermeable and ions and molecules require special membrane transporters to pass through it. The inner membrane folds are known as cristae.

The outer membrane is a relatively simple phospholipid bilayer, containing protein structures called porins which render it permeable to molecules of about 10 kilodaltons or less (the size of the smallest proteins). Ions, nutrient molecules, ATP, ADP, etc. can pass through the outer membrane with ease.The inner membrane is freely permeable only to oxygen, carbon dioxide, and water. Its structure is highly complex, including all of the complexes of the electron transport system, the ATP synthetase complex, and transport proteins. The wrinkles, or folds, are organized into lamillae (layers), called the cristae (singlular: crista). The cristae greatly increase the total surface area of the inner membrane. The larger surface area makes room for many structures than if the inner membrane were shaped like the outer membrane. The membranes create two compartments. The intermembrane space, as implied, is the region between the inner and outer membranes. It has an important role in the primary function of mitochondria, which is oxidative phosphorylation.

In these respects the structure of mitochondria helps it carry out the function. As an example without certain benefits of the membranes it will not be ably to do some of the things it does to its full potential.