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
배아는 초기 발달 단계에서 중요한 역할을 합니다.bae-a-neun chogi baldal dangyeeseo jungyohan yeoghal-eul hamnida.The embryo plays an important role in the early stages of development.