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06.10.2015, 21:51 | |
Plant life Plants are very
important for man's life. They supply us with different food products and
fibre. Domestic animals use plants as fodder. Plants grow and
develop in the soil. They obtain the necessary nutrients from the soil and air. Minerals and
nitrogen are obtained by the plants from simple salts in watery solution.
Carbohydrates are synthesized by plants from carbon dioxide which is in the
atmosphere and water. The source of energy for the process of photosynthesis
is sunlight. The principal parts
of the plants are the root system, stems,
leaves, flowers, fruits and seeds. All these parts
have different functions but they are all very important for plant growth and
development. Plants may be
annuals, biennials and perennials. Annual plants produce seeds the first year.
Biennials produce seeds the second year. Perennials produce seeds during many
years. Seeds germinate at different temperatures. The optimum temperature for
rye, wheat, oats and barley is about 20°—25°C. In order to grow and develop well
plants must have good soil and climatic conditions. They must have enough water
nutrients, heat, air and light. One of the most
important tasks of the collective farmers
is to properly till the soil.
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