癌症是严重威胁人类健康的疾病之一。引起细胞癌变的内在因素是() A.细胞中酪氨酸酶活

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问题:

癌症是严重威胁人类健康的疾病之一。引起细胞癌变的内在因素是()

A.细胞中酪氨酸酶活性降低

B.致癌因子激活原癌基因

C.长期受到电离辐射或X射线照射

D.霉变或熏制食物中所含有的致癌物质

考点:高中生物细胞的分化、癌变、衰老和凋亡细胞的分化、癌变、衰老和凋亡题库
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The little boy entered the house unhappily. His mother was  1 cakes in the kitchen. She smiled as she  2 ,but stopped when she saw his face.“Tyler,  3 happened? Is everything okay?”
“Nothing is okay,Mom,” said the boy.” Today, in our science lesson, Mrs Green talked about the 4 .The whole world is getting dirtier and many animals and plants are dying, She wants us to think of something we can do to help. I thought all the way home, but there is  5 I can do to make a difference.”
“Let me tell you a  6 ,”the mother said after thinking  for a while .“ One morning a man was walking down a beach, there he saw thousands of dying starfish(海星) covering the beach, they were pushed up by the   7 . and it was too far for them to make their way back by  8 . The man shook his head as he walked along,“What a pity!So many starfish will die on the beach.” The man felt very  9 for those starfish . He went on walking and just at that time he was  10 to find a boy in front who was throwing the starfish back into the sea as  11 as he could. “How silly you are! My  12 ,” the man said.“There are so many starfish, and can you throw all of them back?” The boy didn’t stop but kept throwing. “  13 I can’t help them all, I can make a difference to this one, and this one, and this one,”said the boy.“Thinking for a moment, the man  14 to help return the starfish to their home. He smiled and said to himself, “Sometimes the biggest lesson in life comes from the   15 person.”
小题1:
A.drinkingB.makingC.sellingD.washing
小题2:
A.turned aroundB.turned downC.turned onD.turned off
小题3:
A.whatB.whenC.whereD.why
小题4:
A.airB.landC.waterD.environment
小题5:
A.somethingB.anythingC.everythingD.nothing
小题6:
A.lieB.jokeC.storyD.way
小题7:
A.windB.rainC.wavesD.sands
小题8:
A.himselfB.itselfC.ourselvesD.themselves
小题9:
A.tiredB.sorryC.happyD.excited
小题10:
A.afraidB.surprisedC.sadD.angry
小题11:
A.slowB.fastC.soonD.high
小题12:
A.fatherB.motherC.sonD.daughter
小题13:
A.OrB.SoC.BecauseD.Though
小题14:
A.beganB.continuedC.forgotD.waited
小题15:
A.shortestB.tallestC.smallestD.biggest
题型:单项选择题

证券公司开展定向资产管理业务,应当遵循以下( )的基本原则。

A.公平公正、诚实守信

B.健全内控、规范运作

C.投资本金安全保证

D.投资风险客户自担

题型:单项选择题

水泥厂有754吨水泥要运到工地,一辆大货车每次运8吨,一辆小货车每次运5吨.两辆货车同时运送水泥,需要运多少次才能把这批水泥运完?

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主板是PC机的核心部件,在自己组装PC机时可以单独选购。下面关于目前PC机主板的叙述中,错误的是()。

A.主板上通常包含微处理器插座(或插槽)和芯片组

B.主板上通常包含存储器(内存条)插座和ROM BIOS

C.主板上通常包含PCI和AGP插槽

D.主板上通常包含IDE插座及与之相连的光驱

题型:单项选择题

终张拉后的24h内,每端各钢绞线的回缩量不应大于()。

A.1mm

B.2mm

C.3mm

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