Question

Of the gradients listed below, which is the most accurate description of the force that ultimately determines the movement of ions across the membrane?

a.chemical gradient
b.potential gradient
c.concentration gradient
d.electrical gradient
e.electrochemical gradient

Answer 1

The electrochemical gradient, which combines both the chemical concentration gradient and the electrical gradient, most accurately describes the force determining ion movement across membranes.

Step-by-step explanation:

Among the gradients listed, e. electrochemical gradient is the most accurate description of the force that ultimately determines the movement of ions across the membrane. An electrochemical gradient is the combined effect of both the chemical concentration gradient and the electrical gradient of an ion. This gradient influences the diffusion of ions such as sodium (Na+) and potassium (K+) across the cell membrane, considering both their differential concentration and the electrical charge difference across the membrane. In the context of living cells, Na+ tends to move into the cell due to both its concentration and electrical gradients, while the movement of K+ is influenced by its concentration gradient driving it outward and the electrical gradient pulling it inward. Ultimately, the electrochemical gradient integrates these two forces to dictate the movement of ions in biological systems such as nerve and muscle cells.

Answer 2

E) electrochemical gradient