纯系
参考答案：
纯系：通过单株选择或连续自交产生的后代，在表现型和基因型上都表现相对一致。
—What were you doing when you heard Malaysian airlines flight lost?
—I my homework.
A．were doing.
B．am doing.
C．was doing.
D．is doing.
肾动态显像基本原理是什么?包括哪些检查?
