From the Praśna Upaṇiśad, Ch. 2 Line 5:
" Prana engages apana in the organs of excretion and generation;"
http://www.swamij.com/upanishad-prasna.htm
From the Praśna Upaṇiśad, Ch. 2 Line 5:
" Prana engages apana in the organs of excretion and generation;"
http://www.swamij.com/upanishad-prasna.htm