Question
The optic nerve is a tract of the diencephalon that is not completely myelinated until:
| A. |
5 years after birth |
| B. |
2 years after birth |
| C. |
1 year after birth |
| D. |
3 months after birth |
Show Answer
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Correct Answer � D Explanation |
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- The axons of the optic nerve are not completely myelinated until 3 months after birth.
- Myelinated axons are normally not found in the retina.
- The optic nerve is not a true peripheral nerve but a tract of the diencephalon; when severed, the optic nerve does not regenerate.
- Myelination in the central nervous system (CNS) is accomplished by oligodendrocytes; oligodendrocytes are not found in the retina.