The double helix structure, DNA, wasn’t discovered until 1953. Can you name any other discoveries made in the last hundred years that have had an impact on our knowledge about life as much as the discovery of DNA? What are some notable scientists that have made major discoveries in the fields of life science?

By water evaporation from the leaves is created a negative pressure at the top of the tree that promotes the ascension  of the water through channels that are called xylem. there are also two molecule forces that are involved: the intra-water molecules cohesion (water molecules stick to each other) and the adhesion when the water molecules stick to the channels they are running in. this is what enables water to go from the roots to the top of a tall tree.