by Chris Brown
Can our bodies handle all the chemicals in our world?
我們的身體應付得了身邊所有化學物質嗎？
Have you ever wondered how your bones know when to grow, and when to stop growing? Or what makes your heart beat faster when you're nervous or excited? These are both examples of processes in your body that are regulated by chemicals called hormones. Hormones are created in organs called glands, and these glands make up the endocrine (內分泌) system.
In a healthy person whose endocrine system is working normally, hormones are constantly moving through the body and affecting how all kinds of tissues grow, how active the immune system is, and how the reproductive system functions. Hormones can even change a person's mood. So what happens if the endocrine system doesn't work properly?
Unfortunately, some of the synthetic chemicals found in pesticides and other industrial products have been discovered to change the way the endocrine system works. If a person is exposed to these chemicals, his body might start producing more or less of certain hormones. Once these substances—called endocrine-disrupting chemicals—get into the environment, they can have drastic effects on the health of animals, and if humans eat contaminated animals, they can be affected, too.
Scientists are doing more research to find out exactly how the human body is affected by different chemicals. However, new chemicals are constantly being invented for different purposes, and it can be difficult to keep up. In the meantime, people around the world have begun to consider controlling the use of pesticides and other products containing endocrine-disrupting chemicals. The Internet can provide you with more ways to avoid using or coming into contact with these chemicals.
1. Why should endocrine-disrupting chemicals be avoided?
(A) They always increase your heart rate.
(B) They affect the rate at which the body produces hormones.
(C) They are poisonous to fish and some plants.
(D) They do not work well as pesticides.
2. What is the main function of the endocrine system?
(A) To transport hormones through the body.
(B) To create new glands when old ones die.
(C) To protect the body from endocrine disruptors.
(D) To extract hormones from food.
3. Where can endocrine-disrupting chemicals be found?
(A) In all rivers that contain fish.
(B) In the glands that produce hormones.
(C) In human bones and muscle tissue.
(D) In some pesticides and in the environment. |
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