下图为根尖结构四部分的细胞，具有很强分裂能力的是_爱下问搜题

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问题选择题

下图为根尖结构四部分的细胞，具有很强分裂能力的是

答案

答案：D

题目分析：A、图A成熟区细胞，成熟区也叫根毛区，在伸长区的上部，细胞停止伸长，并且开始分化，表皮一部分向外突起形成根毛，根吸收水分和无机盐的主要部位，故不符合题意；

B、图B是伸长区细胞，伸长区在分生区上部，细胞逐渐停止分裂，开始迅速伸长，是根伸长最快的地方，是根深入土层的主要推动力，能够吸收水分和无机盐，故不符合题意；

C、图C是根冠细胞，根冠位于根的顶端，属于保护组织，细胞比较大，排列不够整齐，像一顶帽子似地套在外面，具有保护作用，故不符合题意；

D、图D是分生区细胞，分生区被根冠包围着，属于分生组织，细胞很小，细胞壁薄，细胞核大，细胞质浓，具有很强的分裂能力，能够不断分裂产生新细胞，向下补充根冠，向上转化为伸长区，故符合题意。

阅读理解

四、阅读：（30分）

A

Robert Spring, a 19th century forger (伪造者), was so good at his profession that hs was able to make his living for 15 years by selling false signatures of famous Americans. Spring was born in England in 1838 and arrived in Philadelphia in 1858 to open a bookstore. At first he prospered(繁荣)by selling his small but genuine collection of early US autographs (亲笔签名). Discovering his ability at copying handwriting he began imitating the signatures of George Washington and Benjimin Franklin and writing them on the title pages of old books. To lessen the chance of detection (被发现). He sent his forgeries to England and Canada for sale, Forgers have a hard time selling products. A forger cannot approach a respectable buyer but must deal with people who don’t have much knowledge in the field. Forgers have many ways of making their works look real. For example, they buy old books and use the aged paper of the title page, and they can treat paper and ink with chemicals

In Spring’s time, right after the Civil War, Britain was still fond of the southern states, so Spring invented a respectable young lady known as Miss Fanny Jackson, the only daughter of General “Stonewall” Jackson. For several years Miss Fanny’s financial problems forced her to sell a great number of letters and manuscripts (手稿) belonging to her famous father. Spring had to work very hard to satisfy the demand. However, all this activity did not prevent Spring from dying in poverty, leaving sharp-eyed experts the difficult task of separating his forgeries from the originals.

56. Robert Spring spent 15 years ________.

A. running a bookstore in Philadelphia B. as owners of old books

C. selling real signatures of famous Americans D. as a forger

57. Why did Spring sell his false autographs in England and Canada?

A. There was less chance that his forgeries would be discovered there.

B. The prices were much higher in England and Canada.

C. There was a greater demand there than in America

D. Britan was Spring’s birthplace.

58. After the Civil War there was a great demand in Britain for ________

A. Civil War battle plans B. southern manuscripts and letters

C. the signatures of George Washington and Ben Franklin D. southern money

59. Which of the following about Miss Fanny Jackson is TRUE?

A. She was Robert Spring’s customer.

B. She was an imaginary person created by Spring.

C. She was a little-known girl who sold her father’s papers to make money.

D. She was the only daughter of General Stonewall Jackson.

选择题

在容积一定的密闭容器中，反应A(?)+B(g)C(g)+2D(g)达到平衡后，升高温度容器内气体的密度增大，则下列叙述一定正确的是

A．正反应是吸热反应，且A不是气态

B．正反应是放热反应，且A是气态

C．加入少量C，物质A的转化率增大

D．改变压强对该平衡的移动无影响