The Correct answer would be e. Mutate; are selected; evolve
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.
Answer: Option B
Explanation:
In a typical energy pyramid the amount of energy that is being transferred is only 10% rest of the energy is lost in the form of heat.
The energy from the sun is converted in the form of chemical energy which is stored in the producers.
10 per cent of this energy is transferred to the next trophic level and rest of the energy is lost in the form of heat. This goes on, there is only a transfer of 10 % energy from the successive levels.
So, if the producers have 200 Kcal/m2/year energy the the primary consumers will have 10% of this energy which is equivalent to 20 Kcal/m2/year and then the secondary consumers will have 10 % of 20 Kcal/m2/year which is equivalent to 2 Kcal/m2/year.
Growth and Maintenance. Share on Pinterest. ...
Causes Biochemical Reactions. ...
Acts as a Messenger. ...
Provides Structure. ...
Maintains Proper pH. ...
Balances Fluids. ...
Bolsters Immune Health. ...
Transports and Stores Nutrients.
The right answer is D) 9 groups of 3 microtubules
Centrioles are the constituents of a so-called centrosome structure: every animal cell has a centrosome, which is made of two centrioles and which together form a functional unit. A centriole consists of nine triplets inclined microtubules, surrounded by a number of proteins.
