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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...
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How do Organisms Reproduce?(Question Answer)

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  How do Organisms Reproduce?(Question Answer) QUESTIONS 1. What is the importance of DNA copying in reproduction?  Answer:  During reproduction, DNA copying ensures that each progenitor cell receives an equal number of DNA. As a result, the species retains its own characteristics. It maintains the continuity of life. In DNA copying, the offspring DNA strands are not exactly the same, resulting in diversity in the organism and contributing to evolution. 2. Why is variation beneficial to the species but not necessarily for the individual? Answer:  Different species of organisms maintain contact with a variety of environmental factors. This is very important to survive in the given situation. Any damage to the environmental condition of the population has a detrimental effect on the population. Only those organisms that are able to survive in such conditions and those which are adapted or suitable to the conditions of the organism can develop a population. So diversity...
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Control And Coordination(Question Answer)

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 Control And Coordination(Question Answer) QUESTIONS 1. What is the difference between a reflex action and walking?  Answer: D ifference between a reflex action and walking are- Reflex Action Walking 1. This is an involuntary action   1. This is a voluntary action   2. It is controlled by the spinal chord   2. It is controlled by the brain   3. Response occurs spontaneously   3. Response is based on thoughts.   2. What happens at the synapse between two neurons?  Answer:  The information, acquired at the end of the dendritic tip of a nerve cell  sets off a chemical reaction that creates an electrical impulse. This impulse travels from the dendrite to the cell body, and then along the axon to its end. At the end of the axon, the electrical impulse sets off the release of some chemicals. These chemicals cross the gap, or synapse,...
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