These plasmids occur naturally in nature; they were discovered in micro-organisms and they also confer some biological properties onto micro-organisms.
这些质粒在自然界中自然存在；它们是在微生物中发现的，它们也赋予了微生物一些生物学特性。
2
In the 1970s, scientists isolated bacterial plasmids.
20世纪70年代，科学家分离出了细菌的原生质。
3
The plasmids caused the cells to turn into iPS cells.