What is the importance of the food crop harvest

BioTOP 3, textbook

B 1 Manual grain harvest with a sickle B 3 Longitudinal section through a grain of grain (scheme) Fruit husk (bran) Glue layer Flour body seedling B 2 The structure of a grain blossom (schematic) Stamen awn stigma glume lemma palea spikelet 84 The importance of useful plants Humans are of plants dependent. Crops not only serve as food, but also as fodder for the livestock. Medicines, spices or luxury goods can be made from some useful plants. How have wild plants been modified by breeding? Most useful plants are grown from wild plants. During breeding, some characteristics of the plants were deliberately changed. For example, the yield was increased by increasing the size of the plants (e.g. apples and other types of fruit and vegetables) or the poisonous and bitter substances contained in the plants were reduced. This made beets edible for the first time. In the case of many plants, such as cereals, the time it takes for a plant to develop has been shortened. The number of seeds in the fruit has been reduced in some plants, such as mandarins or grapes. When breeding the useful plants, emphasis was also placed on variety through different shapes (e.g. different types of cabbage). Grain cultivation The seeds of some wild grasses were valued by humans around 10,000 years ago. These were the wild forms of today's cereal varieties. People began to selectively multiply grasses by sowing them. As a result, they had to return to their fields at least at harvest time. As a result, people eventually settled down. The grain harvest used to look very different than it does today. Field workers cut the stalks of grain with small hand sickles ( B 1). Many grains fell on the ground. They then had to be collected by hand. The wild grasses were changed through breeding. The grains stayed in the ear when the stalks were cut. The cut stalks were tied together. Then the grains had to be knocked out of the ears with flails. Today grain is grown in monocultures. When the grain is ripe, the ripe grain must be removed from the husks ( B 2). This is done during harvest with the help of combine harvesters, which thresh the grains from the ears and tie the straw into bales. The grains are cleaned in the mill. With white flour, the starch from the flour body is mainly used ( B 3). You remove the fruit shell and the seedling, as this can quickly become rancid. With wholemeal flour, the fiber-rich fruit husks (bran), the adhesive layer and the vitamin-rich seedling are ground together. The seedling has the nutrients for the first growth processes of the station operation ay7a94 For testing purposes only - property of the publisher öbv

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