题干

下列关于动物体内酶和激素的叙述,正确的是(  )

①激素和酶的功能都具有专一性      ②它们都是蛋白质

③都是由内分泌细胞分泌的          ④有的动物细胞既能产生激素又能合成酶

⑤能产生酶的细胞不一定能产生激素   ⑥能产生激素的细胞不一定能产生酶

⑦激素产生后一般作用于其他细胞.

A:①②⑤

B:④⑤⑥⑦

C:①④⑤⑦ 

D:①②③⑤⑥

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C

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    Maria Mitchell was born in 1818 during a time when many people thought that woman did not need to learn . But , Mitchell's father thought that both boys and girls should go to school .1 he tutored her at home as well as sent to her to school .

    Mitchell's father , recognizing her interest in astronomy (天文学) at early age , encouraged her interest and taught her how to use a telescope . As an 2 she worked as the first librarian at the Nantucket Atheneum library from 1836to 1856 , all the while still looking at the sky at night , studying the stars and the planets.

    In October 1847, Mitchel saw a bright star through the telescope . She was sure that she had 3seen that star before. Excited , she ran to tell her father . She carefully wrote notes about the star. The next night , it looked as if the” star” had 4It also seemed to have a tail (尾巴)!Now , Mitchell was sure that she had found a comet , not a star.

    At eh time , the king of Denmark was offering a prize to the first person to find a comet that could only be seen through a telescope . Mitchell won the prize! It was a gold medal . But , she won something else too . She won people's respect when they saw that she was 5her work . Later , the American Academy of Arts and Sciences voted her in as its first female member .

    In 1856, a new college just for women opened . It was called Vassar College , and Mitchell became a professor there . She was the first female professor to teach astronomy , or the science of stars and planets . Because of her , female students learned that they could be scientists too . Women could make valuable 6to help understand our world .