THE MOLECULAR BASIS OF INHERITANCE
DNA MAKES RNA MAKES PROTEIN
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a lack of nutrients
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exposure to radiation
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an increase in the blood pH
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exposure to moderate temperatures
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Detailed explanation-1: -A nucleotide change in the DNA that does not result in an amino acid change in the protein is called a “synonomous” or “silent” mutation (see Figure 3.3).
Detailed explanation-2: -Mutations in a gene can result in a change in the sequence of amino acids such as in frameshift mutations and in missense and nonsense mutations occurring in point mutations. However, point mutations can also lead to silent mutations.
Detailed explanation-3: -"one gene, one enzyme” is also incorrect, because some genes code for proteins such as collagen or elastin, which have a structural role in the body rather than as catalysts in metabolism, so they are not enzymes.
Detailed explanation-4: -Mutations are changes in a DNA sequence, and they can occur due to radiation or other types of DNA damage. If mutations occur in the part of a gene that encodes a protein (the coding region of a gene), they can change the amino acid sequence of that protein.