29. The kind of communication that is occurring between the
cells below is known as endocrine communication. Essentially, what happens is
that a cell creates a hormone or other molecule which is stored in a vacuole.
When a stimulus is received, the vacuole moves to the cell surface membrane
and dumps the hormone into the blood stream via exocytosis. The hormone then
travels a distance through the circulatory system until it arrives at its target
cell. The hormone diffuses into the target cells and they are stimulated to
do something as a result.
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Slichter