medulla

• اسم يشير إلى الجزء الداخلي من عضو أو بنية في الحيوان أو النبات، مثل النخاع المستطيل أو لب العظم أو لب الكلية أو النخاع الشوكي.

A noun referring to the inner part of an organ or structure in animals or plants, such as the medulla oblongata of the brain or the medullary sheath surrounding nerve fibers.

جمع شاذ

1. White fatty substance around nerve fibersC1formalscientific

   A fatty material that surrounds the core of certain nerve fibers, forming a medullary sheath that aids in the transmission of nerve impulses.

   الميالين

   • The medulla insulates axons, allowing faster signal transmission.
   • Damage to the medulla can disrupt nerve function.
   • Multiple sclerosis attacks the medulla of nerve fibers.

   المرادفاتmedullary sheathmyelinmyelin sheath

2. Medulla oblongata (brainstem)C1formalmedical

   The lower, hindmost part of the brain, which connects to the spinal cord and controls vital autonomic functions such as breathing and heart rate.

   النخاع المستطيل (جذع الدماغ)

   • The medulla oblongata regulates breathing and blood pressure.
   • An injury to the medulla can be life-threatening.
   • The medulla is essential for maintaining basic life functions.

   المرادفاتmedulla oblongatamyelencephalon

3. Inner core of an organ or structureB2formalscientific

   The central or deeper part of an organ or tissue, such as the inner region of a kidney or the pith of a plant stem.

   لب الكلية

   • In plants, the medulla stores nutrients and provides structural support.
   • The renal medulla is responsible for urine concentration.
   • The medulla of the adrenal gland produces stress hormones.

   المرادفاتcentercoremarrowpith

   الأضدادcortex