among cattle having horns is a recessive trait cattle without horns which are called polled cattle are common suppose a horned male mates with a polled female their offspring are polled on maturity two cattle on the f1 generation mated their offspring are a mix of polled and horned cattle

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.