One of the methods by which a plant produces another plant of its own kind, is by production of seed. Seed plants reproduce by a tiny grain of pollen (microspore) growing into an almost invisible plant that produces sperm cells. When these unite with the egg of the plant grown from the megaspore, the large green plant that we know starts developing. Before the development has progressed very far, the new plant becomes completely enclosed in a sturdy case which protects it until it can find a favourable time and place for further development. Until its growth is resumed, the little plant lies dormant as a seed!
The most conclusive example for survival of seed is provided by the Arctic lupin (Lupinus arcticus) gathered from Yukon in Canada by Harold Schmidt in 1954. Carbon dating showed the seeds may be 8000 – 13,000 B.C. But they were germinated in 1966!
Seeds vary greatly in size, shape, pattern and colour. Only a very small number of the worlds seeds, are planted by man. Nature has devised ingenious methods to assure their distribution. Forest seeds travel varying distances before landing to take root. The largest single seeded fruit, that of the double coconut (Lodoicea maldivica) of Seychelles, in the Indian Ocean. It weighs about 20 kg! The smallest seed is produced by an orchid!
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Every seed has three essential parts. The most important is the embryo or tiny plant. The second is nourishment stored in the endosperm and the third, seed coat, which protects the embryo and other contents. The embryo must break through, before growth actually begins. For this there must be present the proper amount of warmth, moisture and oxygen. A shortage or excess of these factors may adversely affect its destiny. It may either lie dormant or decay in the soil.
Dolphins
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Most Venomous Snake
The most conclusive example for survival of seed is provided by the Arctic lupin (Lupinus arcticus) gathered from Yukon in Canada by Harold Schmidt in 1954. Carbon dating showed the seeds may be 8000 – 13,000 B.C. But they were germinated in 1966!
Seeds vary greatly in size, shape, pattern and colour. Only a very small number of the worlds seeds, are planted by man. Nature has devised ingenious methods to assure their distribution. Forest seeds travel varying distances before landing to take root. The largest single seeded fruit, that of the double coconut (Lodoicea maldivica) of Seychelles, in the Indian Ocean. It weighs about 20 kg! The smallest seed is produced by an orchid!
Dolphins
Sea Mammals
Most Venomous Snake
Discussions over the origin of life on Earth are bound to start some intense, emotional debates. But just because it’s a subject that may be very personal for people doesn’t mean we should stop trying to find possible new answers.
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