位于糖酵解、糖异生、磷酸戊糖途径、糖原合成及糖原分解各条代谢途径交汇点的化合物是
A．1-磷酸葡萄糖
B．6-磷酸葡萄糖
C．1，6二磷酸果糖
D．3-磷酸甘油醛
参考答案：B
解析：[考点] 糖代谢各途径的联系
[分析] 6-磷酸葡萄糖是糖酵解、糖异生；磷酸戊糖途径、糖原合成及糖原分解各条代谢途径的交汇点。其他化合物如1-磷酸葡萄糖、1，6二磷酸果糖不参与磷酸戊糖途径，而3-磷酸甘油醛又不参与糖原合成和糖原分解，只有6-磷酸葡萄糖参与上述四条代谢途径，通过它使四条代谢途径相互联系。
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| It's only after three weeks into a new job that I made a serious mistake. My boss called it "extremely embarrassing" in a company-wide e-mail - which, 1 , he wrote because he felt he needed to explain that what I did was something 2 in the company should ever do. I wish I 3 give a good excuse for what I did. At the very least, I wish I could explain it somehow - 4 it on youth, inexperience or ignorance. Unfortunately, I'm 5 , experienced and I know better. 6 I work with some very kind and compassionate(富于同情心的) people. For the past couple of days many of them have taken time to 7 by my desk and offer comfort, encouragement and support. Some have shared with me similar 8 they have made. Evidently I'm not the only " 9 " person here. One of the exchanges I had this week was with Lois, the much-honored, much-respected professional who 10 the desk right next to mine. Lois was completely 11 about her work, and to be honest I was a little nervous about how she would 12 to such an extremely embarrassing incident. As I expected , Lois didn't pass over the 13 when she saw me the next day. She mentioned it directly, 14 with empathetic consideration. She listened to my 15 . Just as I was ready to express my regrets, she brought my self-pity partly to a(n) 16 . "It happened", she said, "There's nothing you can do to 17 that. It happened. But it's over now. It's 18 . It's in the past. You need to let it go, and move on." And with that she returned her 19 to her work, as if to say, "We're done here." I beat myself up for weeks. At such times I need to remember those 20 words: It's over. It's done. Let it go. And mostly, move on. | ||||
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