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.
Picture of a Action Potential. The first step in the action potential is for the neuronâs membrane potential to reach the threshold. This change in the membrane potential can be caused by a variety of factors including excitatory stimulation by another cell or neuron.hen the membrane potential reaches its peak, the action potential is attained, and the sodium channels become refractory and no more sodium ions enter the cell. Potassium ions continue to leave the cell, and the membrane potential slowly decreases towards the resting potential.