Second messengers is produced when Ligand and Receptor bind together within the cell receiving the signal . Second messengers are small molecules or ions that relay signals from one location in the cell (plasma membrane to interior of the cell), which can affect the expression of specific Genes or cell behaviours within the receiving cell (Signal transduction) 
Examples of Second messengers
Consequences of using second messengers
First, during the generation of second messengers, the siganl may be amplified significantly. Each activated receptor molecule can lead to generation of many second messengers, so even a low concentration of signal in the environment can yield a large intracellular signal and response. Second, second messengers can diffuse into other organelles freely, which could influence other cell functions. Third, Cross talk alter the Concentration of common second messengers within the cell. When inappropriate cross talk happened, it can cause uncontrolled change in second-messenger concentration .
- ↑ Hardin J, Bertoni G. and Kleinsmith L.J.(2012) Becker's World of the Cell, 8th edition, Pearson International, Page 392
- ↑ Hardin J, Bertoni G. and Kleinsmith L.J.(2012) Becker's World of the Cell, 8th edition, Pearson International, Page 393
- ↑ Berg J.M, Tymoczko J.L. and Stryer L.(2012) Biochemistry, 7th edition, W.H.Freeman and Company, page 416
- ↑ Berg J.M, Tymoczko J.L. and Stryer L.(2012) Biochemistry, 7th edition, W.H.Freeman and Company, page 416-417