life process is a process of yagna ,

soul is s fire in the homa kundam ,

prani's body is homa kundam

fuel is food intake..

digestion is like burning

homam is the process of evolution from lower state to higher state

iron , calcium are inert

but when body consumes they become blood and bones, ie life substances

once the body’s capability reduces, it dies , but jeeva flame continues, it goes into new body

this is how life, death, life, death cycle continues

sloka ‘’aham annam…..’’ ie I am food , when food is taken by me, the food becomes me … hence prani takes food , not once, but life long

, all lower bodies  gradually, by repeated rebirth ultimately become the fire that is soul ..hence births and deaths happen for bodies..