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.
The answer is D. It allows population to become genetically different
Answer:
It is the center of the solar system.
It is made up mostly of gases, not solids.
It is the most massive object in the solar system.
Explanation: The sun is only about 4 billion years old so the 3rd one is incorrect, and the last one is incorrect because the Sun is made up of mostly hydrogen
Answer:
(a) The grains which are termed as millets are Amaranth, Barnyard, buckwheat, kodu, sorghum, bajra, Kangani, and Ragi.
(b) The following are the advantages of millet due to which they are given more preference than wheat and rice:
1. Millet's are free of gluten, a protein digestion of which is very difficult by the body.
2. When we compare the protein content of rice, wheat and millet, it is found that millet has high protein content.
3. In all aspects of components of nutrients called as carbohydrates, proteins, fats, minerals and vitamins, millet is in prime position and is also easy to digest.
Answer:
The answers are:
C danimeletion
B dna - rna - amino acid - protein - genetic expression
