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克隆
Nearly all living organisms have parents in which they were reproduced and born through various stages of the life cycle. Whether it is a human being with a mother and a father or a chicken hatching from an egg, most living organisms have male and female parents. Some living organisms also form from one parent such as when a single-celled amoeba splits into two to reproduce offspring.
几乎所有的生命体在生命周期的不同阶段都有双亲孕育和培养。无论是有父母双亲的人类还是从一只从鸡蛋孵化而成的鸡，大部分生命体有两性亲代。也有一些生物体形成于单一亲代，例如单细胞变形虫分裂成两个从而繁衍后代。
However, there is a process which is much different in producing offspring called cloning. Cloning is the process when scientists take DNA from an animal cell and then place it or implant it into an egg cell taken from another animal. Before placing though, the DNA from the cell receiving it is removed.
然而，克隆这种繁殖后代的方法大相径庭。克隆是科学家在动物细胞提取DNA然后将其放入或植入其他动物卵细胞的过程。在植入之前，受体细胞内的DNA被移除。
An example of cloning, which made history in 1997, was when scientists successfully cloned a sheep. The new sheep's name was Dolly, and she was not born in the usual manner. Instead, she became an exact copy of her mother, similar to an identical twin. It would be nearly the same as taking the DNA from the son of a mother, placing the DNA in the egg cell of another woman, but first removing the woman's own DNA, and then allow the growth of the new cell in the woman. Nine months later there would be an exact copy of the mother's son born to the woman.
克隆史上的首例是科学家在1997年成功克隆羊。取名为多莉的克隆羊以非常规方式孕育而成。然而，她与其母本完全一致，类似于同卵双生。这与采集儿子母亲的DNA后放入另一个女人的已除去其本身DNA的卵细胞中，然后新细胞的在女人体内生长。九个月后女人便产下与其儿子母亲完全一致的男婴。
In the case of cloning, a father is not needed. In the first successful cloning of an animal the DNA molecule had all of the information needed to create a clone, Dolly. The DNA molecules contains the genetic code, which is basically directions for the new offspring. Normally, a new organism gets half of this code from the father and the other half from the mother. When these two cells are joined together they divide millions of times and then grow into the millions of cells which form the body of the animal. Each cell of the body has a copy of the genetic code and all it would need is an egg cell to grow.
克隆不需要父本。第一个成功的动物克隆中，DNA分子携带了克隆羊多莉所需的所有信息。 DNA分子中包含的遗传密码基本就是新生子代的方向。通常一个新的有机体得到父母亲双方各一半的遗传密码。两个生殖细胞结合后经过上百万次分裂生成数百万个细胞，构成了动物体。体内每一个细胞都复制了遗传密码，而它所需要的不过是孕育其生长的卵细胞。
So with cloning one of those cells is used and then the cell is simply placed in to the egg cell of the carrier. In the sheep example, the carrier was a female sheep. For Dolly, a single cell was used from the udder of her mother. The DNA in her mother's cell was removed and then transferred to an egg cell of another sheep. About five months later Dolly was born without a father and a copy or clone of her mother.
因此克隆就是将亲本的体细胞中的一个植入载体的卵细胞中。利用多莉母亲的乳房的一个细胞，将该细胞的DNA移植到另一只羊的卵细胞。大约五个月后，没有父亲的多莉出生，与其母亲完全一致，是其母的克隆。
Though no humans have ever been fully cloned, human embryos have been cloned. Currently it may not be taking place, but in the future it may happen, but today it is rare. In the movies about Jurassic Park, cloning took place to create the dinosaurs, though it was a fictional movie, much of the science behind the process can be real.
虽然没有完全的克隆人，但曾有克隆的人类胚胎。克隆人目前难以实现，但将来却可能成真，但至今仍然罕见。侏罗纪公园的电影中，克隆用于创造恐龙，虽然这是一个虚构的电影，该过程后的.科学大多是真实的。
Though there are fully developed human clones, other fully developed animals have been cloned besides sheep. They include the rhesus monkey, pig, cattle, cat, rabbit, deer, horse, a few others, and of course mice. Cloning also involves many, many failed attempts before it becomes successful. For instance, Dolly the sheep was not born until after 276 failed attempts. The only true successful cloning takes place when identical twins are born, but they came from a father and a mother. The cloned animals may also experience health problems.
尽管有发育完全的人类克隆，除了多莉羊外其他发育完全的动物克隆，如猕猴，猪，牛，猫，兔，鹿，马等等，当然也有老鼠。克隆成功前还有很多失败的尝试。例如，多莉是276失败的尝试后才出生的。唯一真正成功的克隆是同卵双胞胎，但他们是源于同父同母。克隆动物也可能会遭受健康问题。
In summary, cloning is basically creating another organism without the father involved, and the clone is an exact copy of the mother with the same genetic code. However, if cloning ever became 100% successful, the clones may look alike, but it would not mean they would behave in the same way.
总之，克隆基本上就是不需要父方生育后代且后代完全复制起母亲。但是，100%成功的克隆，即使外表相似，但并不意味着它们的行为会一致。
The respiratory system of the human body is responsible for the distribution of the air inhaled and exhaled throughout a person's life. The respiratory system includes the nose, throat, voice box, wind pipe, and lungs.
呼吸系统
人体的呼吸系统负责人一生吸入和呼出空气的气体交换。呼吸系统包括鼻、喉咙、喉头、气管和肺。
Each time a person inhales, or breathes in air, several kinds of gases enter the body. The most important is oxygen because it keeps a person alive, and the cells of the body need it for energy and growth. The air enters through the nose and mouth and the lungs fill up and then empty out. When the air is inhaled there are tiny hairs in the nose called cilia that filter the air. The air is also warmed and moistened as it travels through the nose. Cilia also protects other parts of the respiratory passages, filtering out dust and other particles.
每次人体吸入空气，会有几种气体的进入人体。最重要的是氧气，因为它是人的生存需要氧气，并且人体细胞需要氧气用于制造能量和生长。空气通过鼻子和嘴进入，填满肺部，然后排空。当空气被吸入时，鼻子内的纤毛过滤空气。鼻腔同样也温润了吸入的空气。而且鼻毛还过滤掉了吸入的灰尘和其他颗粒。
The inhaled air travels through the windpipe, which is called the trachea. The human body contains two lungs. The lungs are pink, mushy, and like a sponge. The lungs are protected by the rib cage and keeps them protected and safe. The lung on the left side of the body is smaller than the right lung, which allows room for a person's heart. Beneath the lungs is a muscle called the diaphragm. It works with the lungs to allow a person to inhale and exhale. When a person breathes in the diaphragm shrinks and levels out as the lungs fill up with air.
吸入的空气穿过气管。人体有两叶肺。肺是粉红色的糊状体，像海绵一样。肺部由肋笼保护。人体左侧的肺比右肺更小，因为左侧的心脏同样需要空间。肺的下部是膈肌。它与肺部协同工作使人体进行吸气和呼气。当一个人的吸气，膈肌收缩，肺部充满空气。
The end of the trachea is located between the two lungs. At the bottom of the trachea are a couple of large tubes called bronchi. The bronchi lead into the lungs. One tube sends air into the left lung, and the other tube sends air into the right lung.
气管的尾部在两肺之间。在气管的底部有几个大的管道成为支气管。支气管与肺部直接相连。一个支气管使空气进入左肺和另一支气管使空气进入右肺。
Once the air travels through the bronchi, it will branch off into smaller tubes called bronchioles. The bronchioles are about the thickness of a hair, and there are about 30,000 in each lung. From the bronchioles the air then continues its journey to tiny air sacs located throughout the lungs. The tiny air sacs are called alveoli.
空气进入支气管后，它将岔开成更小的细支气管。细支气管约为与头发粗细相当，每个肺约有30,000个细支气管。进入细支气管空气再继续穿过遍布肺部的微小气囊。而微小气囊被称为肺泡。
The 600 million alveoli are covered with very tiny blood vessels called capillaries. It is in this area of the lungs between the alveoli and capillaries the exchange of air takes place. Alveoli allow the air to pass into the blood cells of the body, first traveling through the heart carried by red blood cells. The oxygen enters the blood through the tiny capillaries. The heart then takes the blood filled with oxygen and sends it out to all the cells of the body.
6亿个肺泡上都覆盖着非常微小的血管称为毛细血管。肺泡与肺泡之间以及毛细血管之间发生的便是肺部的空气交换。肺泡让空气进入人体血细胞，首先就是通过红血细胞将空气运送到心脏。氧气通过毛细血管进入血液。然后心脏吸收充满氧气的血液并将其运输到到身体的所有细胞中。
When a person exhales or breathes out everything will happen in reverse. The diaphragm relaxes and the lungs become smaller. The cells in the body have received the oxygen it needs, but carbon dioxide must leave the body. This time, wastes enter the alveoli through the capillaries, back through the bronchioles and bronchi, and then the trachea and out through the nose and mouth. The air is warm because it heats up as it travels through the body.
当一个人呼气或吐气则一切相反。隔膜松弛，肺部变小。体内的细胞已接收其所需的氧气，但二氧化碳必须排出身体。此时，废物通过毛细血管进入肺泡，并回到细支气管和支气管，然后通过气管、鼻子和嘴排除。呼出的空气因为穿过体内而变得温暖。
Finally, the lungs are also important for talking. The larynx is located above the trachea, which is often called the voice box. Vocal cords across the larynx open and close, and then vibrate, to create the sounds as air flows between them. The amount of air exhaled determines the loudness of a sound.
最后，肺部对于发声也很重要。喉位于气管，这一部分也被称为喉头。喉头的开合以及声带的振动使得其间的空气以及人体发声。呼出的空气的量决定了声音的响度。
In summary, there are many parts of the respiratory system working together to distribute oxygen throughout the body, as well as the lungs being necessary for a person's ability to talk. It is important to keep the lungs healthy and strong.
呼吸系统是许多器官协同作用将氧气分散到身体的各个部分，而肺也是一个人发声的重要器官。保证肺部的健康和强大是非常重要的。
