The mitochondrion (plural mitochondria) is the site of cellular respiration and the production of adenosine triphosphate (ATP). They are double membrane-bound organelles and the two membranes can be seen in the lower of the two images - arrowed). Most are torpedo shaped, about 10 µm long and 0.5 µm diameter, however the shape can be quite variable. The inner membrane of the mitochondrion is highly folded into structures called cristae (cr on images below) that may be lamellar or tubular in form. The inner compartment of the mitochondrion is known as the matrix. Each mitochondrion has its own complement of DNA, a feature that is used by molecular biologists to explore evolutionary relationships of organisms. Mitochondria are not static organelles, they move about the cell, can change shape, and can divide. The lifespan of a mitochondrion is shorter than that of the cell.
n = nucleus on image above
Last Modified: Wed, 21 Jun 2017 11:20:48 SAST