Which cell type supports and protects neurons?

• A. Microglia
• B. Astrocytes
• C. Ependymal cells
• D. Oligodendrocytes

Answer: (B)

Astrocytes provide both structural support and protective regulation for neurons. They help form the blood–brain barrier with their end-feet around capillaries, which shields neurons from potentially harmful substances while controlling what gets into the brain tissue. They also maintain the extracellular environment by buffering potassium ions, clearing excess neurotransmitters from synapses, and supplying metabolic support (such as lactate) when neurons are active. After injury, astrocytes contribute to repair and scar formation, helping protect surrounding tissue. Other glial types have different roles—microglia act mainly as immune cells that remove debris, oligodendrocytes insulate axons with myelin, and ependymal cells line the brain ventricles and assist with cerebrospinal fluid dynamics—so astrocytes are the ones most directly involved in both supporting and protecting neurons.