题目

One evening after dinner, Mr. and Mrs. Bond called a family meeting. “We’ve had to make a  41  decision,” Mr. Bond announced. “You see, your mother has been offered a post as co-director of a TV station in Chicago.   42  , the station is not here . After   43  long and hard about it, we’ve  44  that the right decision is to move to Chicago.”     Marc looked  45  , while his sister Rachel breathlessly started asking when they’d be moving . “It’s surprising but exciting!” she said. Marc simply said, “I can’t leave my   46   . I’d rather stay 抗生素作为治疗细菌感染的药物，其高效性和巨大的经济价值使抗生素工业经久不衰。其中青霉素的发现和应用具有划时代的意义。(1)青霉菌发酵产生青霉素。青霉菌的新陈代谢类型是_________，青霉素是青霉菌的________代谢产物。(2)在生产和科研中，常选用处于_________期的青霉菌作为菌种或研究材料，因为此时的青霉菌代谢旺盛，__________和__________比较稳定。(3)对青霉菌菌体生长情况的测定：取一定体积的发酵液，经离心分离、反复洗涤后，__________，再计算发酵罐中菌体的总重量。