Một gen cấu trúc có chứa 2880 liên kết hiđrô, có G = 20% tổng số Nu của gen. Mạch đơn thứ nhất của gen có chứa 276 Nu loại X và 21% Nu loại A. a) Tính số Nu từng loại trên gen và trên mỗi mạch đơn của gen. b) Nếu gen trên bị đột biến làm cho tổng số liên kết hiđrô trong gen đột biến chỉ còn 2878 liên kết. Hỏi gen trên đó xảy ra đột biến gì?

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Dịch tiếp (đừng tra google dịch r copy ra sửa lại nha): Your heartburn drugs may be giving you allergies, study suggests When heartburn or ulcer pain strikes, drugs can target stomach acid to calm bellies and offer relief. But a new study suggests the medications may come with a hive-inducing side effect: allergies. After analyzing health insurance data from more than 8 million people in Austria, researchers found that prescriptions of anti-allergy medications surged in those who were prescribed stomach acid inhibitors, a class of drugs that includes proton-pump inhibitors and H2 blockers. The findings, published Tuesday in the medical journal Nature Communications, suggest that disrupting the stomach's delicate balance of acids and enzymes may cause our immune systems to go haywire, triggering allergies that didn't previously exist. "We need to have the general awareness that the stomach has an important digestive function, and it has a kind of sterilizing function," said Dr. Erika Jensen-Jarolim, the study's lead author and a professor at the Medical University of Vienna. "What we get in terms of food and bacteria is actually denatured and degraded in normal stomach function," she told CNN. "When you take anti-acids, this function is impaired, and we have a wide-open window, and many things enter the intestines that are not good." It's not entirely understood how the medications contribute to allergies, but one explanation may be that reduced stomach acid allows undigested food to sneak out of our stomachs. Our immune systems, in turn, can see those foods as a threat.

Làm và chỉ rõ đáp án lấy từ câu nà trog bài giúp em với ạ Choose one which you think fits best after reading the selection. The cause of headaches, whether they are common kind of tension or migraine headaches, or any other kinds, are usually the same. During periods of stress, muscles in the neck, head and face are contracted so tightly that they exert tremendous pressure on the nerves beneath them; headaches, taking many forms from a constant, dull pain to an insistent hammering result. Although at least 50% of American adult are estimated to suffer one or more headaches per week, it is the 20 million migraine sufferers who are in special difficulties. Migraines, which are mostly suffered by women can involve tremendous, unrelieved pain. Migraines, which may also be caused by stress, can occur in people who bottle up their emotions and who are very conscientious in their performance. Escaping from stressful situations, being open with one’s feeling, lowering one’s expectations can help reduce the stress and so cut down on those headaches which can not be “helped” by aspirin and other non - prescription painkillers. 1. It can be restated from the passage that: A. tension or migraine headaches are common to all people. B. headaches can have a variety symptoms. C. tension or migraine headaches are suffered by at least 50% of American adults. D. headaches always produce the same result 2. During the period of stress A. the neck, head and face are contracted. B. some nerves have great pressure put on them. C. a constant dull pain always results. D. some important muscles experience hammering. 3. In America A. a majority of adults has at least one headache a week. B. only women suffer migraines. C. over 20 million men suffer migraines. D. a majority of the headaches suffered are migraine headaches. 4. A restatement of the last sentence of the first paragraph could be: A. Women suffer tremendous, unrelieved pain when they have migraines. B. All sufferers of migraine, usually women, can experience great, continuous pain. C. Female migraine sufferers experience great, continuous pain. D. Migraines are associated with tremendous, unrelieved pain for the women who experience them. 5. According to the author, migraines can be caused by A. expectation of stress. B. being too worried about doing a job. C. escaping from one’s emotions. D. lowering your experience in life.