Vedic texts refers the Life Energy in the body as "Prana". Death is defined as moving out of this life energy "Prana" from the body.
Prana is divided to 5 major parts and each of these is related to following 5 Planets -
1. Pran - Venus
2. Apan - Saturn
3. Saman - Mars
4. Udan - Mercury
5 Vyaan - Jupiter
Each of the 5 pranas have different functions in body, however it is said that upon death Prana is first to leave the body and followed by other pranas.
Vedic text describe that all other pranas eventually gets submerged in Vyaan and it is the job of Vyaan to move the soul or jeeva from one life to another. So basically all Jeevas are carried in to new life by Vyaan Vayu ruled by Jupiter. No wonder Jupiter is called as Jeeva Karaka.