A.網(wǎng)狀纖維和網(wǎng)狀細(xì)胞 B.網(wǎng)狀纖維和膠原纖維 C.網(wǎng)狀纖維和成纖維細(xì)胞 D.膠原纖維和網(wǎng)狀細(xì)胞
A.胎兒的骨髓 B.卵黃囊血島 C.胎兒的肝臟 D.胎兒的脾臟
A.細(xì)胞大小 B.核的形態(tài) C.有無特殊顆粒 D.胞質(zhì)量的多少