Physiology

According to Yoga Science, man is actually a combination of Five levels. Each of these levels is called a 'cell' or Kosha. We are all essentially 'Soul' - a pure consciousness. But this soul is surrounded by five cells or kosha. These are

1. Annamaya Kosha or Physical Body

2. Pranamay kosha or Energy Body

3. Manomaya Kosha or Mind Body

4. Vijnanmay kosha or Intuitive Body

5. Anandamay Kosha or Bliss Body

These five cells are our body. The first three are thick or gross bodies, which are easily understood. The latter two are subtle or thin bodies, which are not easily understood but these are much stronger than the gross body. Each of these five cells is a transformation of matter. They are changeable but the soul is immutable. 

These five cells have no permanent base. They are the cover. The soul is covered by these five cells. Just as a knife or a sword is covered within a cell or sheath, so is the nature of the soul covered behind these cells, and that is why they are called cells. But the soul that resides above these cells or panchakoshas is free from all veils.