Câu 16. Áp suất thẩm thấu ảnh hưởng đến vi sinh vật vì A. gây co nguyên sinh, tb vi khuẩn không phân chia được B. đẩy mạnh tốc độ các phản ứng sinh hoá trong tế bào vi sinh vật. C. tăng hoạt tính enzim. D. gây đột biến hoặc gây chết các tế bào vi khuẩn. Câu 17. Yếu tố vật lý ức chế sự sinh trưởng của vi sinh vật có hại trong quá trình muối chua rau quả là A. nhiệt độ. B. ánh sáng. C. độ ẩm. D. độ pH. Câu 18. Yếu tố vật lý ức chế sự sinh trưởng của vi sinh vật có hại trong quá trình ướp đường trái cây là A. nhiệt độ. B. Áp suất thẩm thấu. C. độ ẩm. D. độ pH. Câu 19. Yếu tố vật lí gây ức chế sinh trưởng của vi sinh vật trong nấu chín, đun sôi thức ăn nước uống là A. nhiệt độ. B. Áp suất thẩm thấu. C. độ ẩm. D. độ pH. Câu 20. Yếu tố vật lí gây ức chế sinh trưởng của vi sinh vật trong phơi, sấy khô nông sản là A. nhiệt độ. B. ánh sáng. C. độ ẩm. D. độ pH. Giúp em với ạ

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It was once believed that being overweight was healthy, but nowadays few people subscribe to this viewpoint. While many people are fighting the battle to reduce weight, studies are being conducted concerning the appetite and how it is controlled by both emotional and biochemical factors. Some of the conclusions of these studies may give insights into how to deal with weight problems. For example, when several hundred people were asked about their eating habits in times of stress, 44 percent said they reacted to stressful situations by eating. Further investigations with both humans and animals indicated that it is not food which release tension but rather the act of chewing. A test in which subjects were blindfolded showed that obese people have a keener sense of taste and crave more flavorful food than non-obese people. When deprived of the variety and intensity of taste, obese people are not satisfied and consequently eat more to fulfill this need. Blood samples taken from people after they were shown a picture of food revealed that overweight people reacted with an increase in blood insulin, a chemical associated with appetite. This did not happen to average-weight people. In another experiment, results showed that certain people have a specific, biologically induced hunger for carbohydrates subsides. Eating carbohydrates raises the level of serotonin, a neurotransmitter in the brain. Enough serotonin produces a sense of satiation, and hunger for carbohydrates subsides. Exercise has been recommended as an important part of a weight-loss program. However, it has been found that mild exercise, such as using stairs instead of the elevator, is better in the long run than taking on a strenuous program, such as jogging, which many people find difficult to continue over a long periods of time and which also increases appetite. 1. Years ago being overweight meant_______. A. being rich B. being stylish C. being physically strong D. being unhealthy 2. The word “crave” in line 8, can be best replaced with A. devour B. absorb C. season D. desire. 3. It can be inferred from the passage that_______. A. overweight people are tense B. These of people don’t eat when under stress C. Weight watchers should chew of something inedible when tense D. 56 percent of the population isn’t overweight. 4. It can be inferred from the passage that_______. A. Thin people don’t enjoy food B. A variety of foods and strong flavors satisfies heavy people. C. Overweight people have an abnormal sense of taste. D. Deprivation of food makes people fat. 5. According to the passage, Insulin A. increase in the bloodstream when people eat large amounts of food B. Can be used to lessen the appetite. C. Causes a chemical reaction when food is seen. D. levels don’t change in average weight people who see food. 6. It can be inferred that for certain people. A. Eating carbohydrates eliminates hunger. B. Carbohydrates biologically induce hunger. C. Carbohydrates don’t satisfy a hunger person. D. Carbohydrates subside when serotonin is produced. 7. What can be said about serotonin? A. it is a chemical that increase the appetite B. Only certain people produce it in their brain. C. it tells the brain when a person is full. D. It neurotransmits carbohydrates to the train. 8. In order to lose weight, it would be a good idea for heavy people to A. jog 3 miles a day and chew on carrot sticks. B. walk up stairs and look a t pictures of food. C. Eat plenty of chewy carbohydrates. D. Avoid stressful situation and eat spicy foods. 9. Which of the following exercises might be best for an overweight person to engage in daily? A. an evening walk B. along swim C. cross-country skiing D. 10-mile bicycle rides. 10. Strenuous programs are believed A. to make people feel like eating B. To be favorite exercise for many people in their attempt at losing weight in the long run. C. To be as good as mild exercises for gaining weight D. to be as easy as mild exercise to continue over long periods of time