Final answer:
Microglia are the neuroglial cells that phagocytize pathogens and increase in presence during brain or spinal cord inflammation. They are resident cells of the brain which regulate brain development, maintenance of neuronal networks, and injury repair.
Step-by-step explanation:
The neuroglial cells capable of phagocytizing bacterial cells and that proliferate when there is inflammation of the brain or spinal cord are known as microglia. Microglia are analogous to macrophages in the rest of the body, handling debris and pathogens through ingestion and digestion. They act as the central nervous system's immune cells and are particularly active during pathological conditions such as infection, playing a significant role in immune surveillance within the brain and spinal cord.