The concentration of ions in the chemical environment surrounding the neurons must be tightly regulated for neurons to function properly. which of the following cells is most responsible for this?
a) satellite cells
b) astrocytes
c) schwann cells
d) oligodendrocytes

Astrocytes.

Explanation:

Astrocytes are the star shaped cells that are present in the brain and spinal cord. The exact constitution of astrocytes in the brain is not known and almost 20% to 40% astrocytes are present in brain.

The astrocytes acts as the blood brain barrier and involved in the process of brain scarring. Astrocytes also regulate ions concentration by propagating the calcium ion channels in response to the stimulus. Astrocytes also generate a response by the calcium dependent release of glutamate.

Thus, the correct answer is option (B).