All cells of the body respond to their environment. For most cell types, the responses can be both general and be related to the cell's particular function. An example of a general response is the regulation of sugar utilization: When sugar is...

In cell physiology, a secondary messenger system (also known as a second messenger system) is a method of cellular signaling, whereby the signaling molecule does not enter the cell but rather utilizes a cascade of events that transduces the signal into...