The amount of DNA that a cell must accommodate is significant—even for smaller organisms. For example, enough DNA is in the typical E. coli bacterium cell to encircle it more than 400 times. To compare, a typical human cell contains enough DNA to wrap around the cell more than 15,000 times. To look at it another way, if the DNA in a single human cell were stretched out and laid end to end, it would measure approximately 6.5 feet (2 meters). Thus, the average adult human body contains 10 to 20 billion miles (16 to 32 billion kilometers) of DNA distributed among trillions of cells. If the total DNA in all the cells from one human was unraveled, it would stretch to the Sun and back more than 600 times.

In 1898, Italian physician Camillo Golgi (1843–1926) first described an irregular network of small fibers, cavities, and granules in nerve cells. It was not until the 1940s—and the invention of the electron microscope—that the existence of the Golgi apparatus was confirmed. Today we know that the Golgi apparatus (frequently called the Golgi body) is a collection of flattened stacks of membranes. It serves as the packaging center for cell products, collecting materials at one place in the cell and packaging them into vesicles, or small sacs, for use elsewhere in the cell or for transportation out of the cell. It’s interesting to note that the number of Golgi bodies varies among cells. For example, protists contain one or a small number of Golgi bodies. Animal cells may contain twenty or more Golgi bodies, while plant cells may contain several hundred Golgi bodies.