下列对免疫说法错误的是 [ ]
A.免疫可以抵抗抗原的侵入
B.免疫总是对人体有益的
C.免疫能识别体内的异常细胞
D.免疫是人体的一种生理功能
答案:B
--Have you got _______ ready for the school trip?
---Not yet. We still have _______ to do.
A.anything; nothing
B.something; everything
C.everything; something
D.something; anything
提供核酸合成原料的代谢途径是
A.糖酵解B.糖异生C.三羧酸循环D.糖原分解E.磷酸戊糖途径