Answer:
The movement of sodium and potassium ions against their concentration gradients (from lower to higher concentration) is known as active transport. This process requires energy in the form of ATP (adenosine triphosphate) to pump the ions across the cell membrane. The energy is used to change the shape of a protein called a sodium-potassium pump, which transports the ions across the membrane.
Step-by-step explanation:
In our bodies, the movement of sodium and potassium ions across the cell membrane is essential for many cellular processes such as nerve transmission, muscle contraction, and maintaining fluid balance. The concentration of sodium ions is higher outside the cell, while the concentration of potassium ions is higher inside the cell.
To maintain these concentration gradients, the cell uses a specialized protein called the sodium-potassium pump, which is embedded in the cell membrane. The pump uses energy from ATP to transport three sodium ions out of the cell for every two potassium ions transported into the cell. This creates a net loss of positive charge from the cell, which contributes to the negative resting membrane potential of the cell.
The movement of ions against their concentration gradient is energetically unfavorable, which is why it requires the input of energy in the form of ATP. The sodium-potassium pump undergoes conformational changes (changes in its shape) as it cycles between binding and releasing sodium and potassium ions, and this is what enables it to transport the ions across the membrane.
Overall, the process of active transport allows our cells to maintain the proper concentration gradients of sodium and potassium ions, which is crucial for many physiological processes.