如图为哺乳动物的胚胎干细胞及其分化的示意图。请回答：
若某药物可抑制肝肿瘤细胞DNA的复制，使用该药物可使肝肿瘤细胞停留在细胞周期的（）期。
参考答案：间
解析：
胚胎干细胞来源于早期胚胎和原始性腺，其中早期胚胎是从动物胚胎发育至囊胚期的内细胞团。白细胞是由骨髓中的造血干细胞分化而来的，所以骨髓的治疗的实质是将上图的造血干细胞移植到患者体内。哺乳动物成熟的红细胞中无细胞核，不能选用作为供体细胞。DNA复制发生在间期，所以抑制肝肿瘤细胞DNA的复制，可使肝肿瘤细胞停留在细胞周期的间期，从而有效地抑制肿瘤细胞的增殖。
考点：本题考查干细胞的相关知识。
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| When my sister and I were growing up, we used to spend summers with my grandparents. Every morning we had to 1 early and help them with the 2 chores (零活). We helped my grandfather 3 the animals and we helped my grandmother in the garden. Then we'd have a big, delicious 4 . We loved the 5 of the hay (干草) in the barn (厩), and we used to 6 there a lot. Once I got hurt when I fell from the hayloft (干草棚), and my grandparents had to take me to the 7 . They were very worried about it and were 8 to let us out of their sight (视野) after that. I can still hear my grandfather's voice, "Now, be 9 in the barn, you two." Now summers come and go, but every summer I remember those 10 times at my grandparents. |
| ( )1. A. sleep ( )2. A. factory ( )3. A. feed ( )4. A. breakfast ( )5. A. shadow ( )6. A. exercise ( )7. A. doctor ( )8. A. peaceful ( )9. A. favorite ( )10. A. helpful | B. get up B. garden B. run B. meat B. form B. play B. parents B. polite B. excited B. free | C. stand up C. farm C. drink C. lunch C. warmth C. fall C. teacher C. easy C. quiet C. noisy | D. act D. house D. wash D. diet D. smell D. raise D. house D. afraid D. careful D. wonderful |