Vital theory supports that the upward movement of water occurs due to activities of living cell. Few important vital theories are as follows:
a) Pumping activity theory:
This theory is given by Godlewaski in 1884. According to this theory, te upwar movement of water occurs through the pumping activity if xylem parenchymatous cells. Tracheids an vessels behave as water reserviour.
b) Pulsating theory :
This theory is given by J.C Boss in 1923. According to him, the upward movement of water occurs due to pulsating activity of inner corticle cell present outside th endodermis. According to this theory, Pulsatory activity of inner cell absorb water from the outside and pump the water into the vessels.
Both above theories are later discarded because the upward movement of water occurs even through xylem. Parenchyma cells and inner corticle cell are damaged or killed by uptake of poison even then the movement of water continue.