Meiosis is the production of sexual gametes like sperm and egg. It is only necessary for sexual reproduction but not growth.
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First off, grab a simple magnet and hold it near your precious metal coin. If the coin is even slightly attracted to the magnet, then you know you have a fake on your hand, as metals with contents of iron and steel are the most likely to be attracted
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Our atmosphere (air) is comprised of 78% of nitrogen. However, this nitrogen is in its elementary state (N₂) and therefore is quite inactive, so the plants can not use it directly. Changing the elementary nitrogen into more reactive forms (NH₃, NO₂, HNO₃) is occurring through the process called nitrogen fixation. It is happening via two processes.
First one is physical nitrogen fixation. When some type of atmospheric physical energy (lightning bolt, for example) reacts with N₂, it splits it in two very reactive N atoms, enabling them to react with oxygen in order to form NO₂.
Second process is biological nitrogen fixation. It's done by bacteria, special bacteria living in the soil, able to use elementary nitrogen for its metabolical pathways resulting in production of ammonia, which can be used by plants. It's noteworthy that bacteria are responsible for about 90% of all nitrogen fixation.
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Energy decreases as it moves up trophic levels because energy is lost as metabolic heat when organisms from one trophic level are consumed by organisms of the next level. More specifically, 90% of metabolic energy is used, so only 10% will be passed down to the next level.
