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Heredity and Evolution (Question Answer)

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  Heredity and Evolution (Question Answer) QUESTIONS 1. If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?  Answer: B trait has arisen earlier because it exists in maximum population. 2. How does the creation of variations in a species promote survival? Answer:  The variations created in a species protects the organism from extinction even in adverse conditions. As a result, the organism gains stability. Helps to adapt to the changing environment of the natural environment. 3. How do Mendel’s experiments show that traits may be dominant or recessive?  Answer:  Mendel used a number of contrasting visible characters of garden peas – round/wrinkled seeds, tall/short plants, white/violet flowers and so on. He took pea plants with different characteristics – a tall plant and a short plant, produced progeny from them, and calculated the percent...

Carbon and its Compounds (Question Answer)

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Carbon and its Compounds (Question Answer) QUESTIONS 1. What would be the electron dot structure of carbon dioxide which has the formula CO 2 ?  Answer:    OR           2. What would be the electron dot structure of a molecule of sulphur which is made up of eight atoms of sulphur? (Hint – The eight atoms of sulphur are joined together in the form of a ring.) Answer:  3. How many structural isomers can you draw for pentane?  Answer: Three structural isomers can be drawn for pentane.   n-pentane iso-pentane neo-pentane 4. What are the two properties of carbon which lead to the huge number of carbon compounds we sea around us? Answer:  The numbers of carbon compounds whose formulae are known to chemists was recently estimated to be about three million. This outnumbers by a large margin the compounds formed by all the other elements put together.The nature of the covalent bond enables carbon to form a large number of compounds...