organic chemistry: repetitive carbon chain of atoms intertwined with each other. - 胸腺嘧啶 個照片及圖片檔基因研究, 醫學實驗室
dna or deoxyribonucleic acid. it is a key element for life and for understanding the evolution of species. - 胸腺嘧啶 個照片及圖片檔