kē / xué / jiā / yán / jiū / luǎn / jīng / cháo / de / fā / yù / jī / zhì / yǐ / liǎo / jiě / yú / lèi / fán / zhí科学家研究卵精巢的发育机制以了解鱼类繁殖Scientists study the development of ovaries and testes to understand fish reproduction