【单选题】Seen in a microscope, the two most dramatic events in the cell cycle are when the nucleus divides, a process called mitosis, and when the cell itself then splits in two, a process called cytokinesis. ...
【简答题】将下列段落翻译成中文 During the 1930s , Enrico Fermi and his co-workers in Italy performed a number of experiments with the newly discovered neutron. He reasoned correctly that the lack of charge on the neutron...
【判断题】Though both hydrogen atom, H, and helium atom, He, have 1s electron configurations in ground states, their average distances of electron(s) apart from the nucleus are not equal.
【单选题】Radiocarbon Dating Nowadays scientists can answer many questions about the past through a technique called radiocarbon(放射性碳), or carbon-14, dating. One key to understanding how and why something happe...