题干

材料一:人类可利用转基因番茄作为生物反应器生产人胰岛素.所用的人胰岛素基因是依据植物“偏爱”的密码子来设计所含的密码子,通过人工合成若干DNA片段,拼接而成,并且在胰岛素﹣COOH端加上KDEL内质网滞留序列,避免胰岛素在植物细胞中的降解.将该基因置于果实专一性启动子的驱动之下通过农杆菌介导的方法转入番茄中,在番茄的果实中表达人胰岛素.

材料二:T4溶菌酶在温度较高时易失去活性,科学家对编码T4溶菌酶的基因进行改造,使其表达的T4溶菌酶的第3位的异亮氨酸变为半胱氨酸,在该半胱氨酸与第97位的半胱氨酸之间形成了一个二硫键,提高了T4溶菌酶的耐热性.

(1)材料一中基因工程操作是采用____ 方法获得目的基因的.获得的人胰岛素基因与人体细胞中胰岛素基因中编码氨基酸的碱基序列不同,但两者所编码的蛋白质中氨基酸序列相同,这是因为密码子具有____ .要想在体外获得大量该目的基因的片段,可以采用____ 技术.

(2)根据上述描述,转基因操作时所用的载体是____ ,载体上的____ 可以转移至受体细胞,并且整合到受体细胞染色体的DNA上.

(3)材料二属于____工程范畴.该工程是指以分子生物学相关理论为基础,通过基因修饰或基因合成,对____ 进行改造,或制造一种____ 的技术.

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答案(点此获取答案解析)

人工合成,简并性,PCR,农杆菌的Ti质粒,T﹣DNA,蛋白质,现有蛋白质,新蛋白质

同类题3

    "Can I see my baby?" the happy new mother asked. When the baby was lying in her arms and she moved the cloth to look upon his tiny face, she gasped(吃力地喘着气). The doctor turned quickly and looked out of the hospital window. The baby had been born without ears. Luckily, time proved that the baby's hearing was perfect. Though the misfortune(不幸)happened to him, he grew into a handsome boy. Yet he felt ashamed when he communicated with others.
    "You should get in touch with other young people," his mother told him, with a kindness in her heart. The boy's father talked with the family doctor about his ears. "Could nothing be done?"the father asked. "I believe I could give him a pair of outer ears, if they could be got," the doctor replied.
    Two years went by. One day, his father said to the son, "You are going to the hospital, Son. Mother and I have someone who will donate the ears you need, but it's a secret."The operation is a big success. Later he married and entered the diplomatic(外交的) service. One day, he asked his father, "Who gave the ears? Who gave me so much? I could never do enough for him or her."
    "You could, my son," said the father, "but the agreement was that you are not to know…not yet."
    The years kept their secret, but one of the darkest days did come. He stood with his father over his mother's casket(棺材). Slowly, the father stretched forth(伸出) a hand and raised the thick, reddish brown hair to reveal the mother had no outer ears.
    "Mother said she was glad she never let her hair be cut," his father whispered gently, "and nobody ever thought mother less beautiful, did they?"