试题与答案

羊的白毛由显性基因B控制,黑毛由隐性基因b控制。下图为一只黑毛母羊与一只白毛公羊

题型:实验题

题目:

羊的白毛由显性基因B控制,黑毛由隐性基因b控制。下图为一只黑毛母羊与一只白毛公羊交配产生后代的遗传图。请根据图回答:

(1)羊的毛色有不同的表现类型,黑色和白色在遗传学上称为             

(2)丙羊的毛色基因组成为      ,其毛色为   

(3)甲羊和乙羊再相配,可能生出黑色小羊吗?    

(4)1997年,“多莉”羊在英国罗斯林研究所的问世标志着现代生物技术——      技术取得重大进展。

答案:

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题型:阅读理解

阅读理解

     Since 1984,   Philadelphia has been cleaning up its act. One by one,   graffiticovered walls are being

changed into outdoor art. So far,   more than 1,   800 murals(壁画)have been painted. Philadelphia now

has more murals than any other American city.

     The walls that were once ugly with graffiti(涂鸦)are now covered with beautiful pictures of historical

heroes and modern art,   thanks to the Mural Arts Program(MAP). Its work makes schools and public

places attractive,   and its citizens very proud. The program began as part of Philadelphia's AntiGraffiti

Network.  Jane Golden is the MAP's artistic director. "When people ask me what our program is about,   "she says,   "I answer them with one word:hope. "Each year,   the MAP offers youth art programs and

workshops.    Some onetime graffiti writers even help paint MAP murals.

     The MAP's work,   says Golden,   is all about developing a sense of community(社区). When a

neighborhood requests a mural,   the MAP works with the people there to develop a message. Some

messages have been "Safe Streets,   ""Love and Care,   " and "Peace Walk".

     The MAP receives up to 50 requests for murals each week. Last year,   the workers painted 140

murals.

     "The making of a mural enters people's collective memory as an extraordinary,   pleasant moment in

neighborhood history,   "says Golden,   who began as a muralist in Los Angeles.

1. What can be the best title for the text?

A. Love,   from Graffiti Writers to Muralists

B. MAP,   a New Company in Philadelphia

C. Jane,   an Excellent Mural Artist

D. Hope,   One Wall at a Time

2. What is the Mural Arts Program in Philadelphia aimed at?

A. Helping the young find jobs.

B. Protecting the neighborhood.

C. Fighting against graffiti.

D. Attracting more visitors.

3. How does the MAP decide on the message for a mural?

A. By having discussions with people in the community.

B. By seeking advice from the city government.

C. By learning from the young graffiti writers.

D. By studying the history of the city.

4. Which of the following best describes the work of the MAP?

A. Difficult.   

B. Dangerous.

C. Experimental.   

D. Successful.

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