Black Friday: lifetime access is on a special offer in the app, until November 30. Black Friday: special offer on lifetime access, until November 30. Download
척삭은 척추동물의 발달 초기 단계에서 중요한 역할을 합니다.Cheoksak-eun cheokchudongmul-ui baldal chogi dangye-eseo jungyohan yeoghal-eul hamnida.The notochord plays an important role in the early development of vertebrates.