A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races. The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this by using at least two races to contain the balls and transmit the loads through the balls.
Organelles are parts of the cell which are adapted and/or specialized for carrying out one or more vital functions, analogous to the organs of the human body (such as the heart, lung, and kidney, with each organ performing a different function).ost important among these is a cell nucleus, an organelle that houses the cell's DNA. This nucleus gives the eukaryote its name, which means true kernel (nucleus). Other differences include: 1  The plasma membrane resembles that of prokaryotes in function, with minor differences in the setup.
The things that make a eukaryotic cell are a defined nucleus and other organelles. The nuclear envelope surrounds the nucleus and all of its contents. The nuclear envelope is a membrane similar to the cell membrane around the whole cell.