相關(guān)習(xí)題
 0  12194  12202  12208  12212  12218  12220  12224  12230  12232  12238  12244  12248  12250  12254  12260  12262  12268  12272  12274  12278  12280  12284  12286  12288  12289  12290  12292  12293  12294  12296  12298  12302  12304  12308  12310  12314  12320  12322  12328  12332  12334  12338  12344  12350  12352  12358  12362  12364  12370  12374  12380  12388  170175 

科目: 來源: 題型:

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

查看答案和解析>>

科目: 來源: 題型:

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(jiǎn)單

查看答案和解析>>

科目: 來源: 題型:

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

查看答案和解析>>

科目: 來源: 題型:

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)

查看答案和解析>>

科目: 來源: 題型:

生態(tài)系統(tǒng)的營(yíng)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)

查看答案和解析>>

科目: 來源: 題型:

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(duì)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(duì)照

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

查看答案和解析>>

科目: 來源: 題型:

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)

查看答案和解析>>

科目: 來源: 題型:

下列對(duì)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)

查看答案和解析>>

科目: 來源: 題型:

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

查看答案和解析>>

科目: 來源: 題型:

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

查看答案和解析>>

同步練習(xí)冊(cè)答案