脊せき索さく

noun, noun which may take the genitive case particle 'no'

notochord

A biological term for the flexible rod-like structure found in the embryos of all chordates, serving as a primitive spinal cord. Used in zoology and developmental biology contexts.

• 脊せき索さくは脊せき椎つい動どう物ぶつの発はっ生せい過か程ていで一いち時じ的てきに現あらわれる構こう造ぞうです。

  The notochord is a structure that appears temporarily during the development of vertebrates.

• ナメクジウオは生しょう涯がいにわたって脊せき索さくを保ほ持じする。

  The lancelet retains its notochord throughout its life.