A:它与体液免疫各自有其独特的作用,又可以相互配合,缺一不可
B:吞噬细胞既可参与细胞免疫也可参与体液免疫
C:效应T细胞产生的淋巴因子能特异性地与抗原结合,杀灭抗原
D:记忆T细胞接受同一种抗原再次刺激时,会迅速增殖分化成效应T细胞
植树造林就是为了获取大量的木材.
Hello! Welcome to my show(欢迎参观我的展览). They're my animals. Look! The lion has got a blue shirt. The tiger has got a red hat. The monkey has got a yellow skirt. The panda has got a green T-shirt. Has the elephant got a brown sweater? No, he hasn't. He has got an orange sweater. That's very funny.
A. B. C. D. E.
三角形三边之比分别为(1)32:2:52(2)3:4:5(3)1:2:3(4)4:5:6,其中可以构成直角三角形的有( )
8×3=____
我们用口诀____
9×3=____
7×2=____
5×5=____