The pH Scale
Since hydrogen ions are positively charged, they alter the charge environment of the molecules they are bonded to.
As a result, they change their shape. This is particularly important for proteins, because their shape is related to their function.
The concentration of hydrogen ions is often expressed in terms of the pH scale:
- Low pH equates to high hydrogen ion concentration
- High pH corresponds to low hydrogen ion concentration
- A substance with a high concentration of hydrogen ions and thus low pH is called an acid
- A substance with a low concentration of hydrogen ions and thus high pH is called a base (or alkaline)
- Substances that enable organisms to regulate their pH in the presence of an acid or base are called buffers.
