Hormones target a limited number of cells or tissues based on the presence of a specific receptor as they circulate in the bloodstream.

The hormones produced by the endocrine system travel via the blood to reach their target cells, tissues or organs. On these target sites, specific hormone receptors are present for the hormones that detect them. The hormones can show their effect only where these particular receptors are present. These receptors can be present on a specific type of cell, a specific type of tissue or a specific type of organ.

Key Points

• Hormones have specific receptors on the target cells, tissues or organs that detect them and the hormones can show their effect.

Key Terms

target cell: a cell that is receptive to a secreted hormone.

endocrine: glands which release secretion directly into the blood

hormone receptor: a molecule that binds to a specific hormone that triggers alterations in cell activity.