| 释义 |
脊索jǐsuǒ某些动物身体内部的支柱,略呈棒形,由柔软的大细胞构成。高等动物的脊柱是由胚胎时期的脊索变化而成的,低等动物(如文昌鱼)的脊索终生不变。{notochord; elongated, rod-shaped structure composed of large, soft cells, forming the primitive supporting axis of the body. The spinal column of higher animals is developed from a similar structure in the embryonic stages, but that of lower animals remains unchanged for life (such as lancelet).} |