MDCAT Biology MCQ #946

When comparing the chemical structure of DNA and RNA, what specific modification is found in the pentose sugar of DNA?

MDCAT Biology MCQ #946

  1. Question 1

    Q1. When comparing the chemical structure of DNA and RNA, what specific modification is found in the pentose sugar of DNA?

    • A) Presence of a hexose sugar instead of a pentose sugar
    • B) Attachment of the nitrogenous base at the carbon-5 position
    • C) Absence of an oxygen atom at the carbon-2 position
    • D) Presence of an extra hydroxyl group at the carbon-3 position

    Answer: Absence of an oxygen atom at the carbon-2 position

    Explanation: Deoxyribose lacks an oxygen atom at the carbon-2 position. Ribose is the standard pentose found in RNA, not DNA.