问题 选择题

下列关于染色体的说法不正确的是(  )

A.遗传物质的载体

B.遗传信息的载体

C.细胞分裂时染色体已经加倍

D.由DNA和蛋白质组成的

答案

细胞核中有一些能被碱性染料染成深色的物质是染色体;染色体由DNA和蛋白质组成的;DNA是双螺旋结构,它是细胞核中储存遗传信息的物质,基因是决定生物性状的DNA片段.细胞核分裂时,染色体的变化最明显.染色体的数量在细胞分裂时已经复制加倍,在细胞分裂过程中,染色体分成形态和数目相同的两份,分别进入两个新细胞中.新细胞和原细胞所含有的遗传物质是一样的.据上分析,遗传信息的载体是染色体的说法是不正确的.

故选:B

阅读理解

Lillian Hanson, a college student, expects to graduate in about two years. What makes Mrs. Hanson different from her classmates is her age-----73 years. She has been studying at college, a few courses at a time, for 27 years.

  When Lillian Hanson graduated from high school, she went to the bank to borrow money for further education. The banker gave her no encouragement. He didn’t think that a country girl should borrow money to go to college. He thought she should be at home doing work in the house or around the farm. So Lillian Hanson went home and raised a family of nine children instead of going to college. Mrs. Hanson never forgot her dream of getting a higher education. When her children were grown, she tried again.

  She finds that it is the hardest part of going back to school at her age to sit in class for long periods of time. Because she is not as quick as she used to be, Mrs. Hanson often gets up and walks around classes to keep from getting stiff(不灵活). At the beginning of a course in using the computer, the other students all stood up to give her a warm welcome when she introduced herself and explained why she was there and what her aims were.

49. Mrs. Hanson couldn’t go to college immediately after she graduated from high school because ____________.

A. she hadn’t got enough money

B. she was a country girl

C. the banker ordered her not to borrow any money

D. the banker thought she should raise a family of nine children

50. The computer students welcomed Mrs. Hanson warmly because ______.

 A. she had got an excellent result in the exam

B. she was good at telling funny stories

 C. they wanted to get her help in their studies

D. they were deeply moved by her spirit

51. Mrs. Hanson is the sort of person who ________.

  A. cares for study very much

B. likes to borrow money from the bank

  C. never misses a chance to talk

D. tries to save any money for her family

52. In which order did Mrs. Hanson do the following things?

  a. she began her studies at college.

  b. She finished high school.

  c. She got married and gave birth of nine children.

  d. She had her 73 rd birthday.

  e. She went to the bank to borrow money.

  A. a c b e d      B. b e c a d   C. b c e d a    D. e d a c b 

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