题干

下列实验材料与实验目的组合最合理的是( )

选项

实验材料

实验目的

A

西瓜果肉

鉴定还原性糖

B

猪成熟红细胞

提取DNA分子

C

洋葱鳞片叶外表皮

观察DNA与RNA的分布

D

黑藻叶片

观察叶绿体

A:A

B:B

C:C

D:D

上一题 下一题 0.0难度 选择题 更新时间:2019-10-23 03:06:34

答案(点此获取答案解析)

D

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    A cat is recovering in California after surviving a 6,500-mile journey across the Pacific stowed inside a Chinese shipping container without food or water. Staff and volunteers have named it “Ni Hao”, which is Chinese for “hello”.

    It was discovered breathing shallowly after a two-week trip across the Pacific Ocean. The cat was seriously suffering from loss of water and starvation when the container was opened in California last week, but was said to be doing well after being sent to the Carson Animal Care Centre in Los Angeles. At first it was too weak to stand, but finally took its first steps. Then it ate a good meal and slept soundly. The cat woke up on Thursday morning, physically in a better condition than 24 hours ago.

     “Ni Hao greeted the medical team with its first meow this morning and is attempting to stand,” said Marcia Mayeda, head of the Los Angeles Department of Animal Care and Control. Aaron Reyes, director of the Department, added, “We finally got to hear its voice. It sounds like a single-engine plane.”

    Ni Hao is expected to be observed for 60 days but afterwards animal workers will look forward to providing it with a good shelter. “It's much better for it to recover in a home environment,” Mr. Reyes said. “It's just like a human being in a hospital so we're hoping to move it.” He added, “Little by little we're getting there. We're hoping that under the treatment and with rest, it'll be able to recover quickly.”

    It was not immediately clear how the cat got into the container.