上游充通大兽 2.A Pair of Nucleic Acid Chains with Complementary SHANGHAI JIAO TONG UNIVERSITY Sequences Can Form a Double-Helical Structure o 大肠杆菌基因组只有一个 DNA双链，每条链的长度 是460万核苷酸 Figure 4.8 Electron micrograph of part of the E.coli genome.Figure 4.8 Electron micrograph of part of the E. coli genome. 2. A Pair of Nucleic Acid Chains with Complementary Sequences Can Form a Double-Helical Structure 大肠杆菌基因组只有一个 DNA双链，每条链的长度 是460万核苷酸