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Matsuzawa wanted to find out the process of ageing could be ______.
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Through using the brain is the best way to maintain good ______.
Genetic engineering is absolutely good for human.
Anthropologists believe differences between traditional and modern societies are that in the old society ______.
Vitamin A is necessary for the body's natural defense system against disease. Vitamin A is needed to help prevent skin and other tissues from drying out. It also produces a light-sensitive substance in the eyes.
People who do not get enough Vitamin A cannot see well in the dark. They may develop a condition that dries the eyes. The condition can result in infections that lead to blindness.
A lack of Vitamin A is a major cause of blindness among children. Health experts estimate that 124 million children around the world do not eat enough foods with Vitamin A.
Vitamin A is found in fish liver oil and in the yellow part of eggs. Vegetables such as carrots and sweet potatoes contain beta carotene, a substance that the body changes into Vitamin A.
Public health campaigns to provide Vitamin A to those who need it have proved costly. And they are not always effective. That has led researchers to try to create foods with the vitamin.
Rice is one of the most common crops grown worldwide. However, normal rice lacks Vitamin A. Researchers at a laboratory in Switzerland found a way to change the genetic material of rice. They added three genes to the rice. The genes produce beta carotene, the chemical that our bodies change into Vitamin A.
The new rice has a golden yellow color. The researchers say 200 grams of the rice have enough beta carotene to provide the necessary amount of Vitamin A.
Biologist Mary Lou Guerinot of Dartmouth College wrote a commentary published with the report in science magazine. She said the rice is an excellent example of the good things that can be done with genetic engineering. However, critics of genetic engineering argue that changing plant genes could increase risks to human health or the environment.
With Vitamin A people won't get any diseases.
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