Hormones are chemical substances produced in one organ that are released into the bloodstream and affect the function of a target organ to respond to a particular hormone, it must?
have receptors that recognize and bind the hormone molecule.

The correct answer is explained below:

Explanation:

Hormones can be defined as certain biological messengers made up of peptides, proteins, sterols, and other substances which are produced in certain organs and released into the blood which carries them to distant parts of the body where they can act on their target organs and bring about alteration in their structure or function.However, for any organ to become the target of a hormone it is essentially necessary that cells of the organ must possess certain receptor proteins which are cognate or recognizable by the hormone molecules.Hormones are capable of bringing about changes in the functioning of the target organ by binding to complementary receptor molecules present on the surface of the cells or inside the cells of the target organ.This binding is brought about by different types of interactions like hydrogen bonding, hydrophobic interactions, electrostatic interactions and Van-der-Waals forces of interaction which activates the receptor.This in turns triggers a signalling pathway from the receptor which is transmitted to the cell interior and this brings about an alteration in the structure or function of the target cell.

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.