2. Прочитайте текст и выполните к нему задания.

PLANTS

Plants have always been of interest to man. It has been shown that at an early period men distinguished and named the kinds of plants they encountered. As civilization developed, men began to arrange and record their knowledge of plants, and in this way botany began. Men's interests were manifold; as time went on, they concerned themselves not only with the kinds and names of plants but also with their structure, their mode of life, then- chemical composition, the functions of their parts and their reproduction.

There is scarcely a plant on earth that man has not tried to use as a medicine, as well as a food. In ancient times men tried out different plants to see which ones helped cure certain diseases. At first they may have used plants with a strong odor or a bit­ter taste. Perhaps they thought that those plants with a bad taste or unpleasant smell would drive out the evil spirits believed to cause disease. Early men probably watched animals to see what plants the animals ate, especially when animals were sick. By trial and error, over the ages, men came to use thousands of plants as remedies for their ills.

Many of the pharmaceuticals currently available to physicians have a long history of use as herbal remedies, including opium, aspirin, digitalis, and quinine. The World Health Organization (WHO) estimates that 80 percent of the world's population presently uses herbal medicine for some aspect of primary health care.

Many plants synthesize substances that are useful to the maintenance of health in humans and other animals. These include aromatic substances, most of which are phenols or their oxygen-substituted derivatives such as tannins. Many are secondary metabolites, of which at least 12,000 have been isolated — a number estimated to be less than 10% of the total. In many cases, substances such as alkaloids serve as plant defense mechanisms against predation by microorganisms, insects, and herbivores. Many of the herbs and spices used by humans to season food yield useful medicinal compounds.

In addition to the use in the developing world, herbal medicine is used in industrialized nations by alternative medicine practitioners such as naturopaths.

The use of herbs to treat disease is almost universal among non-industrialized societies. A number of traditions came to dominate the practice of herbal medicine at the end of the twentieth century:

• The "classical" herbal medicine system, based on Greek and Roman sources

• The Siddha and Ayurvedic medicine systems from various South Asian Countries

• Chinese herbal medicine and others.

Задания:

1. Дайте письменные ответы на вопросы:

1). When did men begin to arrange their knowledge of plants?

2). How did men in ancient times learn to use (dry out) different plants to cure certain diseases?

3). What substances do many plants include?

4). What sources is the “classical” herbal medicine system based on?