medullated

Thân thiện

A medullated nerve fiber transmits signals quickly along its insulated sheath.

Definition

1. Adjective:
   • (Of neurons) covered with a layer of myelin: Describes a nerve fiber (axon) that is insulated by a fatty white substance called myelin. This sheath increases the speed at which electrical impulses travel along the nerve cell.

Usage Examples

• Adjective:
  • The peripheral nerves contain both medullated and non-medullated fibers.
  • In the central nervous system, medullated axons appear white, forming the "white matter."
  • The rapid transmission of signals is a key function of medullated neurons.

Advanced Usage

• Technical/Medical Context: The term is almost exclusively used in specialized fields like neurology, neuroanatomy, and histology. It is a precise descriptor for the physical state of a nerve fiber.
  • The biopsy showed a loss of medullated fibers, consistent with the diagnosis.

Variants and Related Words

• Myelinated (Adjective): This is a more common synonym in modern scientific English. "Medullated" and "myelinated" are often used interchangeably.
  • Myelinated axons conduct impulses faster than unmyelinated ones.
• Myelin (Noun): The fatty insulating sheath itself.
  • Diseases like multiple sclerosis damage the myelin.
• Unmyelinated/Non-medullated (Adjective): Describes nerve fibers lacking a myelin sheath.
  • Non-medullated fibers are responsible for slower, continuous conduction.

Synonyms

• Myelinated: Having a myelin sheath (the most direct synonym).
• Sheathed: Covered with a protective layer (a more general term).

Antonyms

• Unmyelinated: Not covered with a myelin sheath.
• Non-medullated: Not medullated.

Học thuật

Adjective

1. (of neurons) covered with a layer of myelin

Từ đồng nghĩa

• myelinated