1氨基酸之间的脱水缩合和脱氧核苷酸之间的聚合作用分别发生在( )
A.叶绿体、核糖体
B.细胞核、线粒体
C.细胞核、核糖体
D.核糖体、细胞核
开始考试练习点击查看答案2下列生物中,除细胞膜外几乎不含磷脂分子的有( )①乳酸菌 ②变形虫 ③肺炎双球菌 ④酵母菌
A.①②
B.②③
C.③④
D.①③
开始考试练习点击查看答案3下列关于DNA的叙述正确的是( )
A.DNA的复制只发生在分裂间期,复制的场所只能是细胞核
B.在每个DNA分子中,碱基数=磷酸数=脱氧核苷酸数=脱氧核糖数
C.DNA分子中,每个脱氧核苷酸上均连一个磷酸和一个含N的碱基
D.一个DNA分子中含有90个碱基则必定含有270个氢键
开始考试练习点击查看答案4根据中心法则和右表所列已知碱基,推测表中的正确密码子为( )<table style="MARGIN: auto 6.75pt; BORDER-COLLAPSE: collapse; mso-table-layout-alt: fixed; mso-table-overlap: never; mso-table-lspace: 9.0pt; mso-table-rspace: 9.0pt; mso-table-anchor-vertical: paragraph; mso-table-anchor-horizontal: margin; mso-table-left: center; mso-table-top: 8.0pt; mso-padding-alt: 0cm 0cm 0cm 0cm" border="0" cellspacing="0" cellpadding="0" align="left" _dj="MsoNormalTable"><tbody><tr style="PAGE-BREAK-INSIDE: avoid; HEIGHT: 10.35pt; mso-yfti-irow: 0; mso-yfti-firstrow: yes"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 114.45pt; PADDING-RIGHT: 0cm; HEIGHT: 10.35pt; BORDER-TOP: windowtext 1.5pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm" rowspan="2" width="153">双链DNA</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 42.55pt; PADDING-RIGHT: 0cm; HEIGHT: 10.35pt; BORDER-TOP: windowtext 1.5pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt" width="57">T</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 10.35pt; BORDER-TOP: windowtext 1.5pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt" width="46">C</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 10.35pt; BORDER-TOP: windowtext 1.5pt solid; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt" width="46"> </td></tr><tr style="PAGE-BREAK-INSIDE: avoid; HEIGHT: 4.15pt; mso-yfti-irow: 1"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 42.55pt; PADDING-RIGHT: 0cm; HEIGHT: 4.15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="57"> </td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 4.15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="46"> </td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 4.15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="46">T</td></tr><tr style="HEIGHT: 11.3pt; mso-yfti-irow: 2"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 114.45pt; PADDING-RIGHT: 0cm; HEIGHT: 11.3pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="153"> 反密码子</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 42.55pt; PADDING-RIGHT: 0cm; HEIGHT: 11.3pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="57"> </td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 11.3pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="46"> </td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 11.3pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="46">U</td></tr><tr style="HEIGHT: 10.85pt; mso-yfti-irow: 3; mso-yfti-lastrow: yes"><td style="BORDER-BOTTOM: windowtext 1.5pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 114.45pt; PADDING-RIGHT: 0cm; HEIGHT: 10.85pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="153"> 密码子</td><td style="BORDER-BOTTOM: windowtext 1.5pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 42.55pt; PADDING-RIGHT: 0cm; HEIGHT: 10.85pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="57"> </td><td style="BORDER-BOTTOM: windowtext 1.5pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 10.85pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="46"> </td><td style="BORDER-BOTTOM: windowtext 1.5pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 0cm; WIDTH: 34.75pt; PADDING-RIGHT: 0cm; HEIGHT: 10.85pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" width="46"> </td></tr></tbody></table>
A.UCA
B.AGU
C.AGU
D.AGA
开始考试练习点击查看答案5落地生根这种植物生长到一定时候,在叶片边缘会长出许多芽体,这些芽体脱落后又会发育成新个体,这种生殖方式是( )
A.孢子生殖
B.出芽生殖
C.营养生殖
D.分裂生殖
开始考试练习点击查看答案6患感冒时,鼻黏膜充血肿胀,堵塞鼻腔,这时吃东西觉得没味。这是因为( )
A.味薷失去味觉功能
B.嗅细胞接触不到食物的气味刺激
C.嗅细胞失去嗅觉功能
D.大脑皮层味觉中枢失去感觉功能
开始考试练习点击查看答案7达尔文进化理论不能解释的问题是( )
A.生物多样性
B.生物的生存斗争
C.生物遗传变异的本质
D.变异的不定向性和选择的定向性
开始考试练习点击查看答案8在西葫芦的皮色遗传中,已知黄皮基因Y 对绿皮基因y为 显性,但在有白色基因F时,则Y和y都不能表达(两基因独立遗传),现有FfYy个体自交,其后代的表现型的种类和比例是( )
A.4种, 9:3:3:1
B.2种,13:3
C.3种,12:3:1
D.3种,10:3:3
开始考试练习点击查看答案9下面关于细胞工程的叙述,正确的是( )
A.叶肉细胞去分化后可形成定形状态的薄壁细胞
B.转基因克隆动物只用到了细胞核移植技术
C.胚胎干细胞和成体干细胞均具有全能性
D.应用动物细胞培养技术可以生产疫苗
开始考试练习点击查看答案10下列关于实验的描述中正确的一组是( )①班氏试剂加入到蔗糖溶液中,加热后出现红黄色沉淀 ②脂肪的鉴定能看到被染成橘红色的脂肪滴③鉴定还原糖时,要先加入班氏试剂甲液摇匀后,再加入乙液 ④蛋白质用双缩脲试剂鉴定呈紫色⑤洋葱根尖装片制作的步骤是解离、漂洗、染色、压片⑥观察洋葱根尖装片发现最多的细胞是前期细胞⑦用30%蔗糖溶液对临时装片作引流后,约5min后可看到洋葱表皮细胞逐渐发生质壁分离的现象。⑧用于对洋葱根尖染色的染液有龙胆紫或醋酸洋红染液⑨滤纸条上色素带的颜色从上到下依次是橙黄色、黄色、黄绿色、蓝绿色
A.③⑤⑥⑧
B.②④⑤⑦
C.①④⑤⑦
D.②④⑤⑨
开始考试练习点击查看答案