biological strain

例句：

1. 1. The study of genetics is essential for understanding the biological strain within a population.
   研究遗传学对于理解一个种群内部的生物学株系至关重要。
2. 2.In this experiment, we are studying the biological strain of bacteria that can survive in different environments.
   在这个实验中，我们正在研究细菌的生物学株系，这些细菌能在不同的环境中生存。
3. 3. The researcher found that the biological strain of the virus had mutated over time.
   研究人员发现，这种病毒的生物学株系随着时间的推移已经发生了变异。