THE MOLECULAR BASIS OF INHERITANCE
GENE MUTATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Cancer is caused by mutations.
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Mutations are never passed to the offspring.
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Mutations only affect one gene at a time.
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Mutations do not help people adapt.
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Detailed explanation-1: -If a person has an error in a DNA repair gene, mistakes remain uncorrected. Then, the mistakes become mutations. These mutations may eventually lead to cancer, particularly mutations in tumor suppressor genes or oncogenes. Mutations in DNA repair genes may be inherited or acquired.
Detailed explanation-2: -Answer and Explanation: The correct answer to this question is B. They always cause a change to an organism’s genotype. Regardless of the cause of the change, a DNA sequence is always altered when it mutates.
Detailed explanation-3: -Genes contain information to make proteins, and proteins control many important functions like cell growth. Genetic mutations can change how proteins function. Some types of genetic mutations change proteins in ways that cause healthy cells to become cancerous.
Detailed explanation-4: -Random, unpredictable DNA “mistakes” account for nearly two-thirds of the mutations in cancers. These mutations occur as a result of DNA copying errors made when normal cells divide. What causes such random DNA copying errors? Human cells are constantly regenerating.