Final answer:
The energy needed for the Na/Glucose co-transporter to move glucose into the cell against its concentration gradient is provided by the electrochemical gradient of sodium ions created by the sodium-potassium ATPase pump in a process known as secondary active transport.
Step-by-step explanation:
The energy input needed to drive the transport of glucose into the cell through the Na/Glucose co-transporter, especially when there is a higher concentration of glucose inside than outside, comes from the electrochemical gradient of sodium ions that is established by the sodium-potassium pump.
In this process of secondary active transport, the sodium-potassium pump uses ATP to move sodium ions out of the cell, creating a concentration gradient. This gradient is then utilized by the sodium-glucose symporter to pull glucose into the cell against its own concentration gradient, as sodium moves down its electrochemical gradient.
Secondary active transport does not directly use ATP to move glucose into the cell, but instead, it harnesses the energy released when sodium ions move down their gradient. Therefore, this clever mechanism of co-transport allows cells to import glucose without expending ATP directly for its transport.