Understanding exactly how the human brain develops and functions is the greatest challenge of modem biology. Most of what we have learned about the organ since the birth of neuroscience more than 100 years ago derives from experiments done on

Understanding exactly how the human brain develops and functions is the greatest challenge of modem biology. Most of what we have learned about the organ since the birth of neuroscience more than 100 years ago derives from experiments done on animals—frequently mice or rats.

准确理解人类大如何进化以及如何工作，这是现代生物学的最大排战。（考点∶复合句的理解与翻译）