A.5ppm B.0.3ppm C.0.1ppm D.1ppm
A.個(gè)體大小 B.有無(wú)齒棘 C.胞核形狀 D.胞內(nèi)結(jié)構(gòu)
A.圓形大核 B.球形小核 C.長(zhǎng)纖毛 D.漏斗狀口