Final answer:
To determine the number of potassium ions passing through a channel with a 2.1 A current, divide the current by the charge of a single potassium ion. This physics calculation illustrates the role of ion channels in cell membranes.
Step-by-step explanation:
The question pertains to calculating the number of potassium ions (K+) that pass through a cell membrane channel when a current of 2.1 A is carried through it. In physics, the charge carried by a single potassium ion (K+) can be found using the elementary charge, which is approximately 1.602 x 10⁻¹⁹ Coulombs.
Knowing the current (I) and the charge (q) of a single ion, one can determine the number of ions crossing the channel per second (n) by the formula I = nq. To find 'n', simply divide the current by the charge of one ion (n = I/q).
For a 2.1 A current, the calculation would be n = 2.1 A / (1.602 x 10⁻¹⁹ C). When computed, this yields a large number of ions crossing the channel every second, as the charge of one ion is extremely small compared to the total current. This emphasizes the efficiency and specificity of the ion channels in cell membranes, as discussed in biology when exploring cell functions and membrane potential.