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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 percentages of tall or short pr

Periodic Classification of Elements (Question Answer)

Periodic Classification of Elements (Question Answer)   QUESTIONS 1. Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.  Answer:  Döbereiner’s triads also exist in the columns of Newlands’ Octaves . Eg- Li, Na, K. If Li is the first element then Na is the eighth element and their properties are the same. Similarly, if Na is considered to be the first element, then the element K will be the eighth element. 2. What were the limitations of Döbereiner’s classification?  Answer:  Only three triads could be identified from among the elements known at that time. Therefore, this method of classification as a triad was not useful. 3. What were the limitations of Newlands’ Law of Octaves? Answer:  The limitations of Newlands' Law of octave are- 1. Newlands' Law of octave was found to be applicable only up to calcium. After calcium, the properties of eighth elements was not the same as the first element. 2. Newlands' knew that there were only