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.
All eukaryotic cells have within them a variety of different structures called organelles. Organelles are small and function much like organs function in a large organism.Some organelles are responsible for gathering cell energy, others for controlling cell activities.ucleus. The nucleus is one of the most important organelles in a cell. It is often the largest organelle in animal cells, but this is not always the case. Nuclei contain the genetic material called DNA that is responsible for controlling and directing all cell activities.