一个用35S标记了的噬菌体侵入细菌体内,经过三次复制后,测得含35S的噬菌体与子代总数的比值是() ["0","1\/4","1\/2","1"]
土壤肥力具有的四个肥力因素是() ["水、肥、气、热","光、肥、气、热","Ph、肥、热、气","光、水、CEC、热"]
目前西药治疗心律失常可能引发() ["新的心律失常","青光眼","脑卒中","心肌缺血","甲亢"]
陆羽对茶道的贡献有哪些?() ["提出定义“茶道”一词","总结茶道技术法则","创立茶道精神","建立完善的中国茶道体系"]
现金收讫章是指用于现金收入()及现金缴款回单。 ["凭证","帐单","回单","依据"]
简述压注成型工艺的优点是什么?