In cells and matrix are arranged in concentric layers around a central canal that contains blood vessels

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.