题干

如图是某对新婚夫妇体细胞染色体组成示意图,下列叙述正确的是(    )

A:图中染色体是由DNA和蛋白质组成的

B:图甲代表的是生殖细胞,因为染色体是成对存在的

C:这对新婚夫妇精子与卵细胞的受精作用发生在子宫内

D:如果该夫妇都是有耳垂(Dd),则他们的独生子女一定是有耳垂的。

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A

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                                                                                                               伟大的谎言
                                                                                                                  张森凤
        这是一对深山里的父子。父亲是个乡村医生,他常教导儿子,做医生讲求的是诚实,有时一句谎言可能会断送病人的生命。打儿子懂事时起,他就没见过父亲讲过半句谎言,父亲的每一句话,对他来说都是真理。
        12岁那年,父亲带着他进山采药。父子俩进入了密林,莽莽苍苍几百里大山,父子俩带足了干粮、帐篷等生活用品,打算在这里多呆一些日子,多采一些好药。谁料就在第三天晚上,一场灾难向他们袭来:一场特大暴雨袭击了密林,然后又爆发一场山洪,大水卷走了他们所有的生活用品,其中包括辨别方向的指南针。
         “我们还能走出密林吗?”儿子问父亲。
         父亲说,能,当然能,虽然没有了指南针,但我们还可以看太阳、看北极星群的方向,饿了,我们可以采野果子吃。只要我们不失去信心,就一定能走出去!
        从父亲的话中,儿子受到了鼓舞。父子俩上路了,他们从太阳的起落中辨别方向。渴了,就喝一口山泉水;饿了,就啃一口野山楂;困了,就躺在厚厚的落叶上睡觉。
        然而,第四天上午,爻一场灾难向他们袭来:一条毒蛇偷袭了父亲,毒液迅速地弥漫了他的全身,他的口中吐出了白沫。看着奄奄一息的父亲,儿子绝望了,没有了父亲这个主心骨,他真不知何去何从。
        这时。密林下,一丛白色的小花映入了父亲的眼帘。父亲微笑了,断断续续地说:“孩子,我们有救了!这是一种……叫‘还魂草’的小花,是专门……医治剧毒蛇毒的,你出山去。找个医生,让他……带着金银花……速来救我……‘还魂草’跟金银花捣在一起,可治……蛇毒……”看到儿子担心的目光。父亲又说,“放心,这种蛇毒,三天之后,才会……死人,你速去速回……”
        看到父亲那么肯定的眼神,儿子深信不疑了。他采下几株“还魂草”,发狠地往密林外跑去。顺着父亲交代的落日的方向,两天后,儿子终于跑出了密林。母子俩一起去镇上找了个医生。可医生只看了那“还魂草”一眼,就摇头说:“这只是一种无名的野萝卜花,根本不能解除任何毒性。金银花虽有解毒功用,但也只能解除茵毒,根本不能解除蛇毒啊!”
        可是母子俩不信,他们带上这两种药草。带着一群人,按照父亲的“三天”期限重新赶回密林时,父亲的尸体发出一股恶臭,早已死去。那个医生也去了,他看了看死尸紫黑的面容,摇摇头说:“这是中了剧毒的眼镜蛇的毒气,三个时辰内必将暴毙而亡!孩子,你父亲是医生,他不会不知道。他是骗了你啊!”
        刹那间,儿子泪如泉涌。如果没有父亲这个谎言。他想他真的能走出密林吗?答案是,不能!他想他会一直陪在父亲身边,因六神无主而困死密林。
谁说谎言可怕?当谎言中融入一股浓浓的亲情时,谎言就会给人无穷的力量,就会变得十分伟大!

同类题4

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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.