19 Down syndrome is a genetic disorder caused by the
presence of an extra chromosome in the body cells of
humans. This extra chromosome occurs in a gamete as a
result of
(1) an error in the process of cloning
(2) an error in meiotic cell division
(3) a gene mutation
(4) replication of a single chromosome during mitosis

Ais the answer for you

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.