植物体中水分运动一般顺水势梯度进行,一个植物细胞的水势变化受细胞膨压影响。以下有关论述正确的有() ["膨压不断下降,水势就不断下降","水势下降至低于细胞外水势,细胞就吸水","正常植物细胞吸水的时候,水势的增加与膨压关系不大","细胞吸水接近饱和时,膨压接近最大,水势小到接近零"]
When recording the wind direction in the weather log,you would report the(). ["direction the wind is blowing toward","direction the wind is blowing from","duration of the maximum gust of wind","wind chill factor"]
RW24型客车空调自动控制系统的温控器采用()作为测温元件。 ["电接点式水银温度计","热敏电阻","铂电阻","感温包"]
被代理机构签到时系统会自动提示信息有未打印的提入客户回单,操作员需打印提入客户回单。
数字电液调节系统的控制方式有几种?各有什么优点?
什么是取向结晶?