Food Fright
Experiments under way in several labs aim to create beneficial types of genetically modified (GM) foods, including starchier potatoes and caffeine-free coffee beans. Genetic engineers are even trying to transfer genes from a cold-winter fish to make a frost-resistant tomato.
A low-sugar GM strawberry now in the works might one day allow people with health problems such as diabetes to enjoy the little delicious red fruits again. GM beans and grains supercharged with protein might help people at risk of developing kwashiorkor. Kwashiorkor, a disease caused by severe lack of protein, is common in parts of the world where there are severe food shortages.
Commenting on GM foods, Jonathon Jones, a British researcher, said: "The future benefits will be enormous, and the best is yet to come".
To some people, GM foods are no different from unmodified foods. "A tomato is a tomato," said Brian Sansoni, an American food manufacturer.
Critics of GM foods challenge Sansoni’s opinion. They worry about the harm that GM crops might do to people, other animals, and plants.
In a recent lab study conducted at Cornell University, scientists tested pollen made by Bt corn, which makes up one-fourth of the U.S. corn crop. The scientist sprinkled the pollen onto milkweed, a plant that makes a milky juice and is the only known food source of the monarch butterfly caterpillar. Within four days of munching on the milkweed leaves, almost half of a test group of caterpillars had died. "Monarchs are considered to be a flagship species for conservation." said Cornell researcher Linda Raynor. "This is a warning bell."
Some insects that are not killed by GM foods might find themselves made stronger. How so? The insecticides used to protect most of today’s crops are sprayed on the crops when needed and decay quickly in the environment. But GM plants produce a continuous level of insecticide. Insect species feeding on those crops may develop resistance to the plants and could do so in a hurry, say the critics. Insects may also develop a resistance to the insecticide Bt.
At the forum on GM food held last year in Canada. GM crops that have been made resistant to the herbicide might crossbreed with wild plants, creating "superweeds" that could take over whole fields.
So where do you stand? Should GM food be banned in the United States, as they are in parts of Europe? Or do their benefits outweigh any of the risks they might carry?
1. Paragraphs 1,2&3 tries to give the idea that
A) GM foods may bring about great benefits to humans.
B) We cannot recognize the benefits of GM foods too early.
C) GM foods may have both benefits and harm.
D) GM foods are particularly good to the kwashiorkor patients.
2. Why is the case of the pollen-sprayed milkweed citied in Paragraph 6?
A) It is cited to show GM foods can kill insects effectively.
B) It is cited to show GM foods contain more protein.
C) It is cited to show GM foods also have a dark side.
D) It is cited to show GM foods may harm crops.
3. What happens to those insects when not killed by the spray of insecticide?
A) They may lose their ability to produce offspring.
B) They may have a higher ability to adapt to the environment.
C) They move to other fields free from insecticide.
D) They never eat again those plants containing insecticide.
4. Which of the following statements concerning banning GM foods is true according to the passage?
A) Underdeveloped countries have banned GM foods.
B) Both Europe and the U.S. have banned GM foods.
C) Most European countries have not banned GM foods.
D) The United States has not banned GM foods.
5. What is the writer’s attitude to GM foods?
A) We cannot tell from the passage.
B) He thinks their benefits outweigh their risks.
C) He thinks their risks outweigh their benefits.
D) He thinks their benefits and risks are balanced.
Key: ACBDA
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Diabetes
Most of the food we eat is turned into glucose for our bodies to use for energy. The pancreas, an organ near the stomach, makes a hormone called insulin to help glucose get into your body cells. When you have diabetes, your body either doesn't make enough insulin or can't use its own insulin well. This problem causes glucose to build up in your blood.
You may recall having some of these signs before you found out you had diabetes.
*Being very thirsty.
*Urinating a lot - often at night
*Having unclear vision from time to time.
*Felling very tired much of the time.
*Losing weight without trying.
*Having very dry skin.
*Having sores that are slow to heal.
*Getting more infections than usual.
*Vomiting.
Two main types of diabetes are Type 1 and Type 2. Another type of diabetes appears during pregnancy in some women. It's called gestational diabetes.
One out of ten people with diabetes' has Type 1 diabetes. These people usually find out they have diabetes when they are children or young adults. The pancreas of a person with Type 1 makes little or no insulin. People with Type 1 diabetes must inject insulin every day to live.
Most people with diabetes have Type 2 diabetes. The pancreas of people with such diabetes keeps making insulin for some time, but the body can't use it well. Most people with Type 2 find out about their diabetes after age 30 or 40.
Some risk factors which make people more likely to get Type 2 diabetes are:
* A family history of diabetes.
* Lack of exercise.
* Weighing too much.
Diabetes can hurt your eyes, your kidneys, and your nerves. It can lead to problems with the blood circulation in your body. Even your teeth and gums can be harmed. And diabetes in pregnancy can cause special problems.
1. This writing is meant to tell people
A) how to avoid getting diabetes.
B) what to pay attention to when they have diabetes.
C) what diabetes is.
D) about the least development in curing diabetes.
2. A person with diabetes may have had all the following signs EXCEPT
A) becoming fatter and fatter.
B) becoming thinner and thinner.
C) having to get out of bed at night and night.
D) feeling like to drink a lot of water very often.
3. Which of the following statements is TRUE?
A) Most persons with Type 1 or Type 2 diabetes are women in pregnancy.
B) Most women in pregnancy may have the danger of getting diabetes.
C) We find more persons with Type 2 diabetes among children than older persons.
D) We find more persons with Type 2 diabetes among older persons than children.
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