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表現(xiàn)型不同的母牛生育出基因型完全相同的牛,產(chǎn)生這一結(jié)果的最可能的原因是(      )

A.試管動(dòng)物培養(yǎng)              B.胚胎移植

C.胚胎分割移植              D.用同一公牛配種

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單克隆抗體與血清抗體相比,優(yōu)越之處在于   (     )

A.單克隆抗體能夠制成“生物導(dǎo)彈”

B.單克隆抗體可以在體外制備

C.單克隆抗體的特異性強(qiáng)、靈敏度高,產(chǎn)量也大大高于血清抗體

D.單克隆抗體的制備過程簡單

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遇海難而漂浮在海面的人,因缺乏淡水,此人                      (  )

A.血漿滲透壓升高,抗利尿激素增加   B.血漿滲透壓升高,抗利尿激素減少

C.血漿滲透壓降低,抗利尿激素增加   D.血漿滲透壓降低,抗利尿激素減少                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   &n

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在悶熱的房間里開會(huì),有的人容易打“哈欠”,其調(diào)節(jié)方式是          (  )

A.神經(jīng)調(diào)節(jié)     B.體液調(diào)節(jié)     C.神經(jīng)—體液調(diào)節(jié)       D.激素調(diào)節(jié)

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生態(tài)系統(tǒng)的營養(yǎng)結(jié)構(gòu)是                                        (   )

A.食物鏈和食物網(wǎng)    B.群落的垂直結(jié)構(gòu)和水平結(jié)構(gòu)

C.群落和無機(jī)環(huán)境    D.物質(zhì)循環(huán)和能量流動(dòng)

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細(xì)胞核具有什么功能?科學(xué)家通過下列實(shí)驗(yàn)(見下圖)進(jìn)行探究:①用頭發(fā)將蠑螈的受精卵橫縊為有核和無核的兩半,中間只是很少的細(xì)胞質(zhì)相連,結(jié)果無核的一半(a)停止分裂,有核的一半(b)能繼續(xù)分裂;②b部分分裂到16~32個(gè)細(xì)胞時(shí),將一個(gè)細(xì)胞核擠入到不能分裂的a部分,結(jié)果a部分開始分裂、分化,進(jìn)而發(fā)育成胚胎。下列敘述中,不正確的是

 


A.實(shí)驗(yàn)結(jié)果可以說明細(xì)胞核與細(xì)胞的分裂、分化有關(guān)

B.實(shí)驗(yàn)①中,b部分細(xì)胞屬于對照組,a部分屬于實(shí)驗(yàn)組

C.實(shí)驗(yàn)②中,a部分的操作與實(shí)驗(yàn)①中形成對照

D.實(shí)驗(yàn)說明細(xì)胞的壽命與細(xì)胞核有關(guān)

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下列關(guān)于蛋白質(zhì)和氨基酸的敘述,正確的是

A.具有生物催化作用的酶都是由氨基酸組成的

B.高等動(dòng)物能合成生命活動(dòng)所需的20種氨基酸

C.細(xì)胞中氨基酸種類和數(shù)量相同的蛋白質(zhì)是同一種蛋白質(zhì)

D.在胚胎發(fā)育過程中,基因選擇性表達(dá),細(xì)胞會(huì)產(chǎn)生新的蛋白質(zhì)

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下列對實(shí)驗(yàn)的相關(guān)敘述,正確的是(    )

A.鑒定蛋白質(zhì)時(shí),應(yīng)將雙縮脲試劑A液和B液混合以后再加入待檢組織樣液中

B.紙層析法分離葉綠體色素的實(shí)驗(yàn)結(jié)果表明,葉綠b在層析液中溶解度最低

C.可用紫色洋蔥在普通顯微鏡下觀察質(zhì)壁分離、的分布

D.健康人的胃液、唾液和甲狀腺激素3種液體樣本都可以和雙縮脲試劑發(fā)生紫色反應(yīng)

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水在生物體內(nèi)是一種良好的溶劑,是各種化學(xué)反應(yīng)的介質(zhì).下列有關(guān)水的說法不正確的是(   )

A.水是生物體內(nèi)進(jìn)行一切生物化學(xué)反應(yīng)的必需條件

B.當(dāng)人體缺水時(shí),血漿的滲透壓會(huì)降低,從而產(chǎn)生渴覺

C.在核糖體上進(jìn)行的生理過程有水生成

D.休眠或越冬的植物體內(nèi)自由水與結(jié)合水的比值下降

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動(dòng)物細(xì)胞工程技術(shù)的基礎(chǔ)是                                               (    )

A.動(dòng)物細(xì)胞融合                             B.動(dòng)物細(xì)胞核移植

C.動(dòng)物細(xì)胞培養(yǎng)                             D.胚胎移植

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