Plants need much more water to survive than animals do, a sunflower must take in 17 times more water than a human of comparable weight. At least 500 pounds of water must be lifted from the roots to the leaves to make a single pound of organic tissue. This tremendous amount of water is required to undergo photosynthesis each and every day of a plant's life. But how does a tree lift hundreds of gallons of water hundreds of feet in the air against the force of gravity? Scientists have developed two theories to explain this "impossible" phenomenon. In the following, I will discuss the theories and show how the pull theory is mo