Which of the following requires the most ATP to move the molecule across a plasma membrane?
A) water
B) a simple sugar, such as glucose
C) a dissolved gas, such as carbon dioxide
D) an ion moving against a concentration gradient

Question

Quizplus · Accepted Answer

Moving an ion against its concentration gradient requires the most ATP because it goes against the natural flow, thus requiring the cell to use energy to push it in the opposite direction. The other options may require some energy to be transported across the membrane but not as much as an ion moving against its gradient.

Which of the Following Requires the Most ATP to Move