题干

下列是某化合物的结构简图,据图回答:

(1)图中④的名称是____ ;图中表示R基的代号是____ .

(2)形成该化合物的生物化学反应叫做____ ,在这个过程中,相对分子质量减少了____ .

(3)组成这类化合物的基本单位的结构通式是____ .

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答案(点此获取答案解析)

肽键,②③⑤,脱水缩合(反应),36,

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    I was a shy girl. I didn't even like to answer the telephone for fear I'd have to talk to somebody I didn't know. I enjoyed the loneliness of exploring nature. However, at school I had to spend all day in the company of others. My escape was reading. I spent a lot of time studying and was rewarded with good grades. My only failure was Spanish—I'd get all. As on my written work and tests, but Ds and Fs on the spoken part.

    Eventually I went to college. During my third year of college, I had enough of being shy and determined to change my outlook and behavior. One day while at school, I noticed an advertisement for positions on the local classical music radio station. I had grown up listening to classical music, and I could easily pronounce names such as Tchaikovsky, Albinoni, and Chopin.

    I had absolutely no background in radio, and absolutely no hope of getting the job. The idea of talking to thousands of listeners in “radio land” terrified me. However, I luckily survived the interview. I was given brief descriptions of symphonies(交响乐)and a public service announcement to read, and a list of composers' names to pronounce. It wasn't hard for me. I left the recording session(录音时段)with a sense of relief and a sense of accomplishment. About two weeks later I actually landed the job. It was a challenging job, but I grew to enjoy it greatly. I began to feel comfortable talking to people.

    Although I now spend many hours each week talking with people, I'm still basically a quiet person. Perhaps it is my soft voice and my quiet nature that helps draw people out as they respond to my questions as I interview them. My former shyness is a fortune, as I can relate to people who feel discomfortable when they talk to newspaper reporters. I still enjoy moments of loneliness and the peace found in nature. But I'm also glad I decided to make a change in my life that has opened many doors and opportunities that I never knew existed.