Signal transduction occurs when an extracellular signaling molecule activates a cell surface receptor. In turn, this receptor alters intracellular molecules creating a response. There are two stages in this process:
- A signaling molecule activates a specific receptor protein on the cell membrane.
- A second messenger transmits the signal into the cell, eliciting a physiological response.
In either step, the signal can be amplified. Thus, one signalling molecule can cause many responses.
Read more about Signal Transduction: History, Environmental Stimuli, Receptors, Cellular Responses, Major Pathways
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