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问题 选择题

下列关于DNA分子和染色体数目的叙述，正确的是[ ]

A．有丝分裂间期细胞中染色体数目因DNA复制而加倍

B．有丝分裂后期细胞中DNA分子数目因染色体着丝点分裂而加倍

C．减数第一次分裂后细胞中染色体数目因同源染色体分离而减半

D．减数第二次分裂过程中细胞中染色体与DNA分子数目始终不变

答案

答案：C

判断题

工资数值项有独立项和非独立项之分，前者如加班补贴、缺勤扣款、应发工资、扣款合计、实发工资等等。()
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单项选择题

Questions 63 TO 67 are based on the following passage:(10分)　　Television,the modern wonder of electronics,brings the world into your own home in sight and sound.And the word‘television’means seeing far.Television works in much the same way as radio.In radio,sound is changed into electromagnetic waves which are sent through the air.Experiments leading to modern television took place more than a hundred years ago.By the 1920s inventors and researchers had turned,the early theories into working models.Yet it took another thirty years for TV to become industry. The influence of TV on the life of people is incalculable:it can influence their thoughts and their way of life.It can also add to their store of knowledge.Educational TV stations offer teaching in various subjects.Some hospitals use TV for medical students to get close-up views of operations. At first television programs were broadcast in black-and-white.With the development of science and technology,the problem of how to telecast them in full color was solved and by the middle 1960s the national networks were broadcasting most of their programs in color. The programs that people watch are not only local and national ones.Since the launching of the first communications satellite,more and more programs are telecast“live”from all over the world. People in San Francisco were able to watch the 1964 Olympic Games in Tokyo.And live telecasts now come from outer space.In 1969,the first astronauts to land on the moon televised their historic “moon walk”to viewers on the earth.Since then,astronauts have regularly sent telecast to the earth.

The development of science and technology made it possible for television programs to_____.

A．be telecast in full color

B．be telecast in San Francisco

C．be telecast in Tokyo

D．be telecast in black-and-white
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