问题
选择题
下列哪一项属于克隆[ ]
A．将鸡的某个DNA分子片段整合到小鼠的DNA分子上
B．将抗药菌的某个基因引入草履虫的细胞内
C．将鼠骨髓瘤细胞与经过免疫的脾细胞融合成杂交瘤细胞
D．将某肿瘤细胞在体外培养繁殖成一个细胞系
答案
答案：D
搜题请搜索小程序“爱下问搜题”
下列哪一项属于克隆[ ]
A．将鸡的某个DNA分子片段整合到小鼠的DNA分子上
B．将抗药菌的某个基因引入草履虫的细胞内
C．将鼠骨髓瘤细胞与经过免疫的脾细胞融合成杂交瘤细胞
D．将某肿瘤细胞在体外培养繁殖成一个细胞系
答案：D
| 阅读上面的材料, 完成下列句子。( 每空一词) | |
| Here are reports of three attacks (攻击). Three swimmers were attacked by sharks (鲨鱼) because they didn't obey (遵守) the safety rules for swimmers.
died. Report 2: Ann was a very good swimmer. She bought a new bright red swimming suit. She was swimming with some friends when a shark attacked her. Report 3: Jack was on holiday in Australia. He cut his foot on the beach. He went swimming the same day and got attacked. | |
| 1. Colin was attacked by a shark and died because he was swimming with two friends very late at ________. 2. It's not a good idea to wear a ________ red swimming suit like Ann, because sharks can see colours. 3. You mustn't go swimming with an open _________. 4. If you see a shark, try to swim ________, with even strokes. 5. You can be _________ only if (只要) you obey the safety rules for swimmers. |