Just because you can contribute to a 401(k) plan doesn't mean you'll be allowed to contribute to an IRA. For a traditional IRA, you must be under 70 1/2 years old at the end of the year.For Roth IRAs, your modified adjusted gross income must fall below the annual income limits.hough you're allowed to contribute to a traditional IRA when you're contributing to a 401(k) plan, you can't deduct your contribution if your modified adjusted gross income is too high. The limits are based on your filing status and adjust annually for inflation.
The initial event of an action potential is the depolarization of the axon due to the inflow of sodium ions. Thus, the option c is correct.
Action potentials are considered an all-or nothing event. Once the threshold potential is reached, the neuron completely depolarizes. As soon as depolarization is complete, the cell resets its membrane voltage back to the resting potential. The Na+ channels close, beginning the neuron's refractory period.