第12题: [单项选择]下列关于补体系统的描述,错误的是() A. 补体系统参与机体的抗感染及免疫调节,是体内重要的免疫效应系统和放大系统 B. 补体性质不稳定,加热56℃30min即被灭活 C. 正常情况下补体系统的含量相对稳定 D. 补体是一组具有酶样活性的球蛋白 E. 补体性质稳定,不易受各种理化因素的影响 参考答案:E
第13题: [单项选择]Paragraph 5 ______. A. The Change in People’s Eating habits B. The Foods Which Grow in Soil C. The Foods Which Were Fed D. The Importance of Fiber E. Today’s Various Kinds of Foods F. Other Aspects of Healthy Eating 参考答案:D