A Common Source of DNA Damage Is the Spontaneous Loss

question 138

Multiple Choice

A common source of DNA damage is the spontaneous loss of the amine group on cytosine, which then transforms into uracil. This occurs at a rate of about 100 times a day. Fortunately, the body produces enzymes able to detect and repair such uracils back into cytosine. Given this information, suggest why DNA differs from RNA in possessing the nucleotide thymine rather than uracil.

• A)If these thymines were uracils, then they would be promptly changed into cytosines.
• B)The DNA has thymine instead of uracil so as to maintain four different types of nitrogenous bases.
• C)The additional carbon that distinguishes thymine from uracil is apparently the label that prevents the conversion of this nucleotide back into cytosine.
• D)all of the above

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Definitions:

Market

A forum where buyers and sellers come together to exchange goods, services, or information.

Goods and Services

Goods and services encompass all the physical items and intangible benefits that are produced and consumed to satisfy human wants and needs.

Factors of Production

Factors of production are the inputs used in the production of goods or services in the attempt to make an economic profit, including labor, capital, land, and entrepreneurship.

Circular-Flow Model

The circular-flow model is an economic diagram that illustrates how households and firms interact through markets for products and resources, depicting the continuous flow of money and resources.