One
substance, other than the secretions from nerve cells, that is used in cell
communication are hormones.
<span>
To
add, <span>a hormone is any member of a class of signaling
molecules produced by glands in multicellular organisms that are transported by
the circulatory system to target distant organs to regulate physiology and
behaviour.</span></span>
To prevent cells from either shrinking or swelling you should keep them in an isotonic solution. Isotonic solution is a solution with equal amount of solute and solvent. Therefore, when cells are placed in such a solution they will not lose or gain water, as opposed to hypertonic (more solute than solvent) and hypotonic (more solvent than solute) solutions.
