The endocrine system shares with the nervous system a role for control and coordination throughout the body. The nervous system and endocrine system should not be considered as entirely separate entities. Some endocrine organs respond to nervous stimuli. The endocrine system is important in the development and maintenance of the nervous system.
Some reflexes involve both systems.
Structurally, the endocrine system comprises a number of separate organs and tissues scattered throughout the body. All the structures have in common the characteristic that they produce one or more hormones . Other structures not listed above also produce hormones, but are not included within the endocrine system. Some hormones are stored, others undergo continuous turnover. There is usually a level of release which can be either increased or decreased.