問題詳情
DNA basically serves as the ___44___of life. Ladder-like and ___45____, a DNA can be found in chromosomes,__46__ compose each cell of a human body. __47_ really important about DNA is that it works like a blueprint,__48___ the cell how to grow into a living organism. DNA is responsible for the variety of species and individuals onthis planet. __49___ the secrets of DNA has led scientists to think they may have the power to create life itself througha process known __50___ cloning. Dolly the sheep was the first animal successfully created in the laboratory by meansof this process.
【題組】44.
(A) building site
(B) building up
(C) building block
(D) building on
參考答案
答案：C
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)