The white bulb is completely normal. It is, indeed, the 'root'.
But, the body sheds hairs every day, and when it does so the root, or this 'bulb' disconnects itself from the base of the follicle, and is shed along with the hair.
Most hairs that humans shed SHOULD have a white bulb on the end, whether you are male pattern baldness or non-male pattern baldness.
After this shed, the follicle goes into a resting state for a few months, then sprouts another 'bulb' and and the process repeats with a new hair.