Escherichia coli, bacilus subtilis and Saccharomyces cerevisiae are being developed as hosts for genetically engineered genes and as such are potentially able to synthesize a range of products.

A. 大肠杆菌
B. 枯草芽孢杆菌
C. 酿酒酵母
D. 噬菌体

This simplicity has led to an obligate requirement for intracellular growth and a heavy dependence on host cell structural and metabolic components.

A. 细胞外的
B. 细胞内的
C. 完整的细胞
D. 不完整的细胞

The finding that bacteria could be infected by viruses began in 1917 with the discovery of bacteria viruses or bacteriophages.

A. 朊病毒
B. 支原体
C. 衣原体
D. 噬菌体

They replicate inside specific host cells by using the biosynthetic systems of the host under the direction of the viral genomes.

A. 繁殖
B. 复制
C. 折叠
D. 重复

species ______________。

chemoorganotrophs _____________。

aerobic _____________。

actinomycetes _____________。

identical _____________。

bacteriophages _____________。