White matter is primarily composed of which structures?

White matter is primarily composed of which structures?

• A. Myelinated axons
• B. Neuron cell bodies
• C. Dendrites
• D. Synapses

Answer: (A)

White matter is defined by its color coming from the lipid-rich myelin sheaths surrounding axons, which speeds nerve conduction. The structures that give rise to this white appearance and function are myelinated axons, produced by oligodendrocytes in the CNS. This is why white matter serves as the communication highways, connecting different gray matter regions and enabling fast transmission between them. In contrast, neuron cell bodies, dendrites, and synapses are primarily located in gray matter, where neural processing and synaptic connections occur. So the best answer is myelinated axons.

White matter is defined by its color coming from the lipid-rich myelin sheaths surrounding axons, which speeds nerve conduction. The structures that give rise to this white appearance and function are myelinated axons, produced by oligodendrocytes in the CNS. This is why white matter serves as the communication highways, connecting different gray matter regions and enabling fast transmission between them. In contrast, neuron cell bodies, dendrites, and synapses are primarily located in gray matter, where neural processing and synaptic connections occur. So the best answer is myelinated axons.