Question #08c44
1 Answer
Secondary messengers in general are messengers that carry messages and trigger processes inside the cell. They are used when the primary messenger cannot pass through the cell membrane.
This is similar to when someone visits you at home. They cannot pass through your door directly, so they ring the doorbell, which makes you come and open the door. Similarly, secondary messengers act on signals from the primary messengers that can't get through the membrane.
Cyclic AMP (cAMP) is a secondary messenger that serves this same purpose. It is usually involved in phosphorylation processes, which basically involves the activation of different processes through the adding of phosphate groups.
It is important that cAMP and other secondary messengers are small so that they can move quickly and activate what they need to activate. If they were very large, then they would probably move slower as they'd be bulkier. Remember, all this needs to happen in an instant. If you touch a hot pan, then you jump back in an instant. That's how quickly this needs to happen. Hence, it would be much more beneficial if the messengers were small and fast.
These two videos might help you get a better idea of how this process works:
Hope that helps :)
