Bluete is a collective term

Encounters with nature 3, textbook

79 The fruit develops from the ovary You learned in the first grade that the seeds of the overcast flowering plants develop from the ovules after the egg cells have been fertilized. The ovary transforms into a fruit. Seed fruit has inedible, lignified fruit husks Seed fruit is the collective term for fruit types whose seeds are eaten. Most of the time, the seeds are enclosed in inedible, lignified fruit coats. The seeds contain a lot of oil, protein and starch and are rich in vitamin E. The seed fruits include, for example, walnuts, hazelnuts and sweet chestnuts. The walnut has unisexual inflorescences and is monoecious. The flowering time is between May and June. Pollination occurs by the wind. The fruits, the walnuts, are nut fruits. The unisexual flowers of the hazel also sit together in inflorescences on one plant. They bloom between the end of January and the beginning of March, even before the leaves appear. The pollen from the male inflorescences is blown away by the wind, sometimes for kilometers. Again and again, pollen grains stick to the stigmas of female inflorescences. After fertilization, nut fruits, the hazelnuts, develop from the ovaries. We also find nut fruits in the sweet chestnut. One to three at a time are wrapped in a spiky fruit cup. When the fruits, also known as chestnuts, are ripe, the fruit cup opens with four flaps. The sweet chestnut has unisexual, purely male inflorescences as well as inflorescences in which male and female flowers are united. It's your turn! The seeds of some seed fruits, such as pine nuts, are not surrounded by any pericarp. Why not? Think or research. Walnut tree, leaves and fruits 111 Broken walnuts 112 Hazelnuts, unripe fruits 113 Flowering sweet chestnuts 114 Sweet chestnuts, fruits 115 Nut fruits contain only one seed and have a woody pericarp. This remains closed until the seed germinates. Nuts are therefore counted among the closing fruits. Ripe hazelnuts 116 Fruits and vegetables Ripe in Austria: October Ripe in Austria: September – October Ripe in Austria: late September - mid-November For testing purposes only - property of the publisher öbv

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