Chakras are just the old way of explaining how bioelectricity is distributed within a human body. Just as good old "electricity", you not only need to have a conductor for it; you need a generator, a distributor, a proper conductor and a receptor that uses it. Now, we may asume that bioelectrity in the human body is generated by absorbing it from air, water, food, the Sun, etc. And how is this bioelectricity distributed, conducted and used within the human body? Sages from all times have insisted that the body stores and distributes this energy via "energy centers" that rotate and distribute this energy where it is required. Hence the term "chakra" or "wheel". You cannot just open an electric cord and "see" the electricity within it.