What modality of ion channel is necessary for the function of the axon and the axon terminal?

Voltage gate

Explanation:

An action potential is a localized change in electrical potential between the ion inside and outside of the nerve fibre when stimulated. The inside becomes positively charged while the outside becomes negatively charged. This is called depolarisation.

The membrane becomes more permeable and because the sodium pump temporarily ceases, causing an influx by diffusion of Na+ into the axoplasm. This raises the concentration of Na+ ions within the axoplasm relative to the outside causing the K+ ions to diffuse out. The movement of this action potential along a nerve  fibre constitutes a nerve impulse.

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.

atp is used for energy.