RAPD
参考答案:
DNA以随机的寡核苷酸序列(通常为10个碱基)作引物,通过PCR扩增,产生不连续的DNA扩增产物,用于检测DNA序列的多态性。
When we get together, we always have a great time ____ to each other. We usually talk about something
interesting. [ ]
A. saying
B. telling
C. talking
D. laughing
进站信号机红灯灭灯后,能否开放引导信号?为什么?