【判断题】只受两个力的作用而平衡的构件称为二力杆。由于二力杆的两个力必沿这两个力作用点的连线,所以二力杆不一定是直杆,也可以是曲杆或其他刚性杆件。()
【单选题】The gene they discovered today __________ all those cases.
【简答题】gene family; gene cluster
【简答题】基因调控(gene regulation or gene control)
【简答题】断裂基因(interrupted gene or split gene)
【判断题】二力杆的杆件可以是直的,也可以是弯曲的。
【单选题】Gene therapy is one of the ________areas of medical research today.