题目

据图回答下列问题. (1)请在精子、卵细胞和受精卵中完成填图. (2)生殖细胞包括和.受精卵内的染色体数目与体细胞内的染色体数目,所以受精卵不是生殖细胞. (3)若A和a分别控制眼皮的双、单,且双眼皮(A)为显性,那图中父亲的眼皮表现为,母亲的眼皮表现为,受精卵发育成的个体将表现为. READING COMPREHENSION   Want to lose weight?Try eating.That’s one of the ways being developed by scientists experimenting with foods that trick the body into feeling full.   At he Institute of Food Research in Norwich, England, food expert Peter Wilde and his colleagues are developing foods that slow down the digestive system, which then sends a signal to the brain that stops appetite.“That fools you into thinking you’ve eaten far too much when you really haven’t,”said Wilde.From his studies on fat digestion, he said it should be possible to make foods, from bread to yoghurt, that make it easier to diet.While the research is still in its early stages, Wilde’s approach to controlling appetite is one that some doctors say could be a key to solving the problem of obesity.   “Being able to switch off appetite would be a big help for people having trouble losing weight,”said Steve Bloom, a professor of investigative medicine at London’s Imperial College, who is not connected to Wilde’s research.Bloom said that regulating appetite through foods is theoretically possible.But Bloom warned that controlling appetite may be very challenging.“The body has lots of things to prevent its regulatory systems from being tricked,”he said.   Wilde’s research makes use of the body’s ways of digesting fat.Fat normally gets broken down in the first part of the small intestines(肠道).When you eat a high-fat meal, however, the body can only digest the fat entirely further down in the intestines, which then causes the body to produce a kind of chemical to stop the appetite.   Wilde’s approach copies what happens with a high-fat meal.He coats fat droplets(滴)in foods with modified proteins from plants, so it takes longer for the chemical that breaks down fat to reach it.That means that the fat isn’t digested until it hits the far reaches of the intestines.At that point, intestinal cells send a signal telling the brain it’s full.Even though the body hasn’t had a high-fat meal, it stops the appetite as if it has.If the fat had been digested earlier in the intestines, no such signal would be sent. (1) According to Wilde’s research, what could people do if they want to lose weight? [  ] A. Eat more bread and yoghurt. B. Trick the body by eating nothing. C. Have foods with fat droplets coated. D. Control their digestive system strictly. (2) The underlined word“obesity”in Para.2 most probably means“________”. [  ] A. being too fat B. eating too much food C. stopping appetite D. being unhealthy (3) What can be inferred about Professor Bloom’s opinion towards Wilde’s approach? [  ] A. It won’t work since the body’s regulatory systems will never be tricked. B. It is sure to switch off the appetite of people with a weight problem. C. It sounds terrible because regulating appetite through foods is not practical at all. D. It’s no that easy to trick the body so more research should be done. (4) Which of the following is TRUE about Wilde’s approach? [  ] A. A kind of chemical is added to make a high-fat meal less fatty. B. Fat is digested earlier and the body sends a signal telling the brain it’s full. C. Fat won’t get broken down in the first part of the small intestines. D. The chemical that breaks down fat will not reach the fat. (5) The passage is written to ________. [  ] A. give advice on how to stop eating high-fat meals B. introduce a research on controlling appetite C. discuss the argument between two professors D. show different ways to trick the body
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