Putting It Together: Cell Communication

Now that we’ve learned about cell communication, let’s watch the process of a single message as the cell passes it along:

We just watched how epinephrine is used as a sample messenger to trigger the release of glucose from cells in the liver. This is an example of phosphorylation, one of the two methods of intracellular signaling. The other method—second messengers—can be seen in Ca2+ signaling in muscle cells, which leads to muscle contractions.

These are just two examples of the many, many body functions that rely on cell communication. As we discussed in opening this module, imagine again what would happen if we could not communicate in society. Now, with your new appreciation of cell communication, imagine what would happen if even a single aspect of that process broke down.


It is tempting to view different topics as completely separate, but in fact the ideas we cover in this course are often connected to one another. If you don’t retain the vocabulary from module to module, those connections can be missed. As you continue on, remember to come back and review the terms you’ve learned in order to increase your depth of knowledge.