Cell Structure and Function

What Is the Role of Mitochondria in Eukaryotic Cells?

Structure of Mitochondria

Mitochondriaglossary term (opens in a new window) are specialized organelles found in eukaryotic cells. The number of mitochondria in cells varies. Most cells contain hundreds of mitochondria. They have an outer and an inner membrane. The smooth outer membrane encloses the organelleglossary term (opens in a new window) and separates it from the surrounding cytoplasm. The inner membrane has a series of deep folds called cristae. This folding increases the surface area of the membrane. The large surface area facilitates the chemical reactions that occur on the inner membrane. Mitochondria are filled with a semifluid matrix that also contains ribosomes and mitochondrial DNA.

Function of Mitochondria

Mitochondria supply energy to the cell. They do this through a process called cellular respiration. In cellular respiration, oxygen combines with food molecules to release energy in the form of adenosine triphosphate (ATP). Cells use this ATP to provide energy necessary for key cellular processes. These, in turn, drive the activities of tissues, such as muscle contraction and nerve impulses.