生物污染
参考答案：
可以引起食物传播疾病的生物污染物，包括细菌、病毒、寄生虫、真菌和生物毒素
The twins in Dalian last year. They here now. [ ]
A. are; were
B. were; are
C. was; are
D. were; was
心动周期的等容收缩期时（）
A.心房压<心室压
B.心房压>心室压
C.主动脉压<心室压
D.心房压>动脉压
E.主动脉压=心室压
