CELL DIVISION
CELL DIVISION AND CANCEROUS CELLS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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In the phosphates
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In the sugars
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In the nitrogen bases of nucleotides
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All of these
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Detailed explanation-1: -An insertion mutation occurs when an extra nucleotide is added to the DNA strand during replication. This can happen when the replicating strand “slips, ” or wrinkles, which allows the extra nucleotide to be incorporated (Figure 2). Strand slippage can also lead to deletion mutations.
Detailed explanation-2: -DNA base pair. Under normal circumstances, the nitrogen-containing bases adenine (A) and thymine (T) pair together, and cytosine (C) and guanine (G) pair together. The binding of these base pairs forms the structure of DNA .
Detailed explanation-3: -Mutations can result from errors in DNA replication during cell division, exposure to mutagens or a viral infection. Germline mutations (that occur in eggs and sperm) can be passed on to offspring, while somatic mutations (that occur in body cells) are not passed on.
Detailed explanation-4: -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).