【单选题】According to the passage, the invention of the visible-light microscope allowed scientists to ______.
B.
develop the electron microscope later on
C.
understand more about the distribution of the chemical elements
D.
discover single-celled plants animals they had never seen before
【单选题】Which microscope does not rely on visible light?
C.
Phase contrast microscope
E.
Transmission electron microscope
【单选题】管状器官的管壁结构由内向外依次是( )。
【单选题】安全标志是提示人们识别、警惕( )因素,对防止人们偶然触及或过分接近带电体而触电具有重要作用。(1分)
【单选题】管状器官的管壁结构由内向外依次是( )。
【简答题】What is a microscope used for?
【单选题】安全标志是提示人们识别、警惕( )因素,对防止人们偶然触及或过分接近带电体而触电具有重要作用。(1分)加油!必过!
【单选题】安全标志是提示人们识别、警惕()因素,对防止人们偶然触及或过分接近带电体而触电具有重要作用。