Answer: B. all the nitrogen obtained by animals come from plants.
Explanation:
Animals are unable to use inorganic bacteria until plants absorb it and then animals get it from the plants so in effect, all the nitrogen obtained by animals comes from plants.
Plants absorb nitrogen in the form of Nitrates which were fixed by bacteria from Nitrites which were further fixed from Ammonium which was fixed from atmospheric Nitrogen all by bacteria.
Answer:
The trends go up in the presence of nutrients.
Explanation:
There is a great relationship between nutrients and photosynthesis because photosynthesis can't occur without without the availability of nutrients. Plants uses carbon from the atmosphere which is a nutrient whereas other nutrients such as nitrogen, phosphorus, potassium etc from the soil with the help of the roots. If these nutrients are available in the surrounding, the plant produced more food during photosynthesis because these nutrients are the food of plants so the trends go up in the presence of nutrients and lowers down in the absence or lower concentration of nutrients.
Group IV of the Periodic Table of the Elements contains carbon (C), silicon (Si) and several heavy metals. Carbon, of course, is the building block of life as we know it. So is it possible that a planet exists in some other solar system where silicon substitutes for carbon? Several science fiction stories feature silicon-based life-forms--sentient crystals, gruesome golden grains of sand and even a creature whose spoor or scat was bricks of silica left behind. The novellas are good reading, but there are a few problems with the chemistry.
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CRYSTALLINE CREATURES? Silicon can grow into a number of lifelike structures, but its chemistry makes it unlikely that it could be the basis for alien life-forms.</span>
Indeed, carbon and silicon share many characteristics. Each has a so-called valence of four--meaning that individual atoms make four bonds with other elements in forming chemical compounds. Each element bonds to oxygen. Each forms long chains, called polymers, in which it alternates with oxygen. In the simplest case, carbon yields a polymer called poly-acetal, a plastic used in synthetic fibers and equipment. Silicon yields polymeric silicones, which we use to waterproof cloth or lubricate metal and plastic parts.
