A cell has a membrane potential of –100 mV (more negative inside than outside) and has 1,000 times more calcium ions outside the cell than inside. Which of the following best describes a mechanism by which Ca2+ enters the cell?
Movement of Ca2+ into the cell through an ion channel down its concentration gradient
Passive diffusion of Ca2+ into the cell down its electrochemical gradient
Cotransport of Ca2+ into the cell with Cl–
Movement of Ca2+ into the cell through a carrier protein down its electrical gradient
Facilitated diffusion of Ca2+ into the cell down its electrochemical gradient
Master Passive vs. Active Transport with a bite sized video explanation from Jason Amores Sumpter