常見例句Chordates are characterized by an endoskeleton. 脊索動物有特征性的內骨骼。Most chordates have a high-pressure, closed circulation with a ventral heart. 大多數(shù)脊索動物循環(huán)具有高壓的、封閉的循環(huán)系統(tǒng),心臟位于腹面。There are about45.000 species of chordates, occupying marine, fresh and brackish water and terrestrial habitats. 有大約45.;000種脊索動物,它們占據(jù)著海、水或淡咸水和陸地的生態(tài)環(huán)境。There are about 45.000 species of chordates, occupying marine, fresh and brackish water and terrestrial habitats. 有大約45.;000種脊索動物,它們占據(jù)著海、淡水或淡咸水和陸地的生態(tài)環(huán)境。The coelom formed from a pocketlike outgrowth of the wall of the archenteron, especially in echinoderms and chordates. 腸體腔由原腸壁的袋裝生長而形成的體腔,尤其存在于棘皮動物和脊索動物中A flexible rodlike structure that forms the main support of the body in the lowest chordates,such as the lancelet;a primitive backbone. 脊索細胞構成的一條縱長可彎曲的桿狀結構,其作用是引導產生神經板,形成軀體的支持軸 返回 chordates