题干

洋葱是二倍体植物,某同学用低温诱导洋葱根尖细胞染色体加倍并获得成功.下列相关叙述中不正确的是(  )

A:低温诱导只能使具有分裂能力的细胞染色体加倍

B:低温诱导过程会使细胞出现不完整的细胞周期

C:根尖细胞分裂中包括细胞核分裂和细胞质分裂两个过程,两者是不同步的

D:低温诱导根尖细胞染色体加倍时,可能发生染色体数目变异,也可能发生基因重组

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D

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    Humans and gorillas shared evolution for 23 million years. Their paths separated only six million years ago. Research on how gorillas communicate can help us understand human language development.

    Understanding how the brain works helps us see a connection between language development and non-verbal signs. These signs or movements include things like the way we move our hands or bodies or the different expressions our faces have in different social situations. A new study on gorillas showed that the right side of the body is controlled by the left part of the brain and it is also the location for language development.

    Two cameras were used to film all of one ape's movements. One of the first results was that gorillas use their right hands more when they are doing actions with their heads or mouths at the same time. This shows that there is a connection between how our brain works and the reason we use one side of our body more than the other. In addition, we can use the results of the study and our knowledge about brains to help us understand more about how language first developed in humans.

    Dr Forrester, who did the study, says the results can be useful in other ways, such as understanding language development in children. For example, some children have serious illness called “autism” which can stop them communicating normally with people. It might be possible to use the same study method to find out which children have this illness when they are very young. Doctors will then be able to start treatment early.