L2.2.2: Hormone Action

• HORMONE ACTION

  ● Hormones circulate to all organs of the body via blood

  ● Target cells / organs — hormone that affects only certain tissue cells or organs

  ○ For a target cell to respond to a hormone, that hormone attaches to protein receptors

  ○ These protein receptors must be present on the cell’s plasma membrane or in its interior

  ○ When this binding occurs, the hormone will influence the workings of a cell
• HORMONE ACTION

  ● Hormone binding alters cellular activity

  ● Hormones arouse cells by increasing or decreasing the rate of normal metabolic process
• HORMONE ACTION

  ● Typically, one or more of the ff occurs:

  ○ Change plasma membrane permeability or membrane potential (electrical state) by opening/closing ion channels

  ○ Activate or inactivate enzymes

  ○ Stimulate or inhibit cell division

  ○ Promote or inhibit secretion of a product

  ○ Turn on/off transcription of certain genes (such as those encoding proteins or regulatory molecules)