Signal Transduction

Signal Transduction
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:
1. A signaling molecule activates a specific receptor protein on the cell membrane.
2. A second messenger transmits the signal into the cell, eliciting a physiological response.

In either step, the signal can be amplified. Thus, one signaling molecule can cause many responses.

More about this:
http://en.wikipedia.org/wiki/Signal_transduction
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SIGNAL TRANSDUCTION
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