SCIENCE
BIOLOGICAL SCIENCES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It’s when an organism adapts to its environment
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It’s when the offspring of two parents is different from each parent
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It’s when the genes mix to create a new combination
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It’s when the DNA sequence changes due to a mistake when it divides during mitosis or meiosis
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Detailed explanation-1: -Mutations result either from errors in DNA replication or from the damaging effects of mutagens, such as chemicals and radiation, which react with DNA and change the structures of individual nucleotides. All cells possess DNA-repair enzymes that attempt to minimize the number of mutations that occur (Section 14.2).
Detailed explanation-2: -An insertion changes the DNA sequence by adding one or more nucleotides to the gene. As a result, the protein made from the gene may not function properly. A deletion changes the DNA sequence by removing at least one nucleotide in a gene.
Detailed explanation-3: -Importantly, new mutations also occur during meiosis, at frequencies much higher than during the mitotic cell cycles. These meiotic mutations are associated with genetic recombination and depend on double-strand breaks (DSBs) that initiate crossing over.
Detailed explanation-4: -(myoo-TAY-shun) Any change in the DNA sequence of a cell. Mutations may be caused by mistakes during cell division, or they may be caused by exposure to DNA-damaging agents in the environment. Mutations can be harmful, beneficial, or have no effect.
Detailed explanation-5: -Somatic mutations occur in non-reproductive cells; they are passed to daughter cells during mitosis but not to offspring during sexual reproduction.