Seed

Article

August 20, 2022

A seed is the reproductive organ of a seed plant that reproduces asexually. The seed consists of the actual embryo, the food store and the shell that protects them. In the embryo, the motifs of the new plant's roots, shoot and first leaves are ready. The food store is protein and fat or starch. The shell protects the seed when it travels to a new place of growth and waits for a suitable germination time, for example the following spring or the start of the rainy season. The size of the seeds varies greatly. The one-seeded fruit of the Seychelles palm (Lodoicea maldivica) weighs up to 20 kg, while one gram of orchid seeds can hold about a million. A seed is produced when the fertilized gamete of a gymnosperm or angiosperm plant matures in conjunction with its parent plant. The emergence of a seed is preceded by flowering and pollination. Seeds can develop inside the fruit and colloquially, some dry fruits are sometimes somewhat erroneously called seeds. Since most plants do not move from their place, seed transport is the best way for them to spread to new habitats. Seeds have evolved a variety of structures to speed dispersal: some have hairs and protrusions to help them spread with the wind (dandelion, maple), some droop in the snow and float on the surface of melting waters (spruce), and some attract animals to collect and hide them (nuts). Humans use the seeds of many plant species to their advantage. Some of the seeds are used directly as food, others yield oils and many, especially seeds of useful and ornamental plants, are collected for growing new plants. Linseed oil is also used in paints, and the fiber that grows in the husk of the cotton seed is used to make textiles.

Nutritional use and restrictions on use

The seeds of cereal plants, called grain or grain, contain the most carbohydrate-rich starch intended as reserve food for the future squirrel. The fatty germ fills only a few percent of the grain. Cereals also have fiber. The seeds of legumes such as beans are high in protein. The seeds of oil plants contain a lot of fat. However, the nutritional use of oilseeds should be limited because they naturally contain heavy metals from the soil, such as nickel, aluminum and cadmium. According to the Finnish Food Agency, adults should therefore not use more than 2 tablespoons (approx. 15 g) of oil plant seeds daily, and it is not advisable to eat the seeds of the same plant several times a week. The dose for children under school age may not be more than half the dose for adults, and it can be increased later gradually as the child grows. Oil plant seeds are not recommended for infants, pregnant women and those who are breastfeeding. Aluminum accumulates most abundantly in sesame, pine and chia seeds, and nickel in sunflower, hemp and pine seeds. Cadmium occurs most in sunflower, flax and poppy seeds, arsenic most in poppy seeds.

See also

Spore

Sources

On topic elsewhere

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