Final answer:
Ions are specifically transported into the cell through facilitated diffusion via carrier (permease) proteins, which move ions across the cell membrane down their electrochemical gradient without the use of energy.
Step-by-step explanation:
One way in which ions are specifically transported into the cell is via carrier (permease) proteins. This process, known as facilitated diffusion, allows ions to move across the cell membrane down their electrochemical gradient without the use of energy. The ion or molecule binds to an active site on a carrier protein, causing the protein to change shape and release the ion or molecule on the other side of the membrane, where it can then return to its original shape. Facilitated transport is specific and allows the selective movement of substances when simple diffusion is not sufficient, particularly for water-soluble substances like ions.
Other methods of ion transport include active transport, which requires energy in the form of ATP and utilizes carrier proteins, channels, or pumps to move ions against their concentration gradient. However, in the context of this question, carrier (permease) proteins are responsible for the facilitated diffusion process described.