Electron;neutron
Because the neutron has no charge with mass.
the electron has a negative charge but no mass, because it is in the electron cloud.
One wouldn’t allow for passive transport. And the other would allow to much. The membrane serves as a gate. Non-permeable would be a solid wall were nothing and no one can get through or get out . Including things like water. And fully permeable would represent no gate at all and would allow to much in and out of the cell.
Answer:
Cyanobacteria, Anabaena and Azotobactor are called Nitrogen fixing bacteria. These bacteria change the nitrogen in the atmosphere into a form that is used by the plants to make proteins. Plants take nitrogen in the form of nitrates. The atmospheric nitrogen is first converted into ammonia after that ammonia is converted into nitrates and this nitrates use by the plants to make proteins.
Both were powerful nations and they served as trading hubs in their respective regions during that time.
