This process of using a biological event like resistance to Ampicillin in order to pick out the cell population that you're interested in is called selection.

这个利用生物特性,如对氨苄青霉素的抗性,来挑出你所感兴趣的细胞的过程叫筛选

耶鲁公开课 - 生物医学工程探索课程节选

Selection can shift a population from life in the trees to life on the ground by tiny steps but only if the right kind of variation is available.

ECONOMIST: A master of evolution takes a last long look at Darwin

Selection on an arboreal ape population will be impotent if variations which improve their terrestrial prospects are sparse.

ECONOMIST: A master of evolution takes a last long look at Darwin

Though the genes in question have yet to be identified, this result suggests they are too abundant to be there by chance in other words they are being kept in the population by natural selection because psychopathic behaviour confers a selective advantage.

ECONOMIST: Evidence that psychopaths are born, not made