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When a sound occurs at a high enough intensity, the bones of the skull vibrate which in turn vibrate the fluid in the cochlea. For this reason, even a person with no ear canals at all will be able to hear loud sounds. This level of hearing loss is called:

Question : Did you identify optimal length in your experiment? In answering this question, explain how you came to the conclusion that optimal length was or was not identified – why does force change with muscle length? Provide at least one mechanistic explanation in answering this question

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Two species are 99% identical in their DNA sequence yet they are quite different in morphology and the way that they interact with their environment. From your knowledge of the principles of molecular genetics, explain how two species can be so phenotypically different when they are so nearly identical in their DNA sequence.