Its called ptyalin the juice that changes some starches to sugar
I truly believe the answer is choice A.
The sodium concentration is higher outside the cell than
inside the cell and the potassium concentration is higher inside the cell than
outside the cell.
Because the sodium-potassium exchange pump moves sodium and
potassium ions in opposite directions, the pump generates concentration
gradients for these ions that are opposite in direction.
Not sure but i think cohesion forces
