题目

免疫球蛋白IgG的结构示意图如右，其中-S-S-表示连接两条相邻肽链的二硫键。若该IgG由m个氨基酸构成，则该蛋白质至少有氧原子的个数是                         A．m-4个           B．m+4个     C．m-2个           D．m+2个 答案：B----- Bob, you have made great progress in doing experiments recently. ------The professor offered me many practical suggestions, so I made ____ few mistakes in my experiments . A. commonly        B. comparatively    C. effectively                 D. separately